Script | Spoken-Tutorial - User contributions [en]

PhET-Simulations-for-Chemistry/C2/Conductivity/English

2022-12-17T03:32:51Z

Vidhithakur:

'''Conductivity'''

'''Author: Vidhi Thakur'''

'''Keywords: PhET simulation,''' '''Conductivity, battery, metals, plastic, photoconductor, valence band, conduction band, band gap, spoken tutorial, video tutorial.'''

{|border=1
||'''Visual Cue'''
||'''Narration'''
|-
|'''Slide Number 1'''

'''Title Slide'''
||Welcome to this spoken tutorial on '''Conductivity.'''
|-
||'''Slide Number 2'''

'''Learning Objectives'''

||In this tutorial, we will learn how,

* Change in voltage makes the electrons move in the circuit.

* Large band gap in plastics do not allow conductivity.

* Shining light on a photoconductor causes it to conduct electricity.
|-
||'''Slide Number 3'''

'''System Requirement'''
||Here I am using

*'''Windows 11 (64 bit)'''.
*'''Java Version 1.8'''.

|-
||'''Slide Number 4'''

'''Pre-requisites'''

'''https://spoken-tutorial.org'''
|| To follow this tutorial, learner should be familiar with topics in High School Science.

Please use the link below to access the tutorials on '''PhET simulations.'''
|-
|| '''Slide Number 5'''

'''Link for PhET simulation'''

Point to
'''https://phet.colorado.edu/en/simulations/conductivity/about'''
|| Please use the given link to download the '''PhET simulation'''.

'''https://phet.colorado.edu/en/simulations/conductivity/about'''

|-
|| '''Point to the file in the Downloads folder'''.
|| I have downloaded the '''Conductivity simulation '''to my '''Downloads''' folder.
|-
|| '''Double click the file to open'''
|| To open the simulation, double-click on the file.

|-
|| '''Cursor on the interface.'''
|| This is the interface of '''Conductivity simulation.'''
|-
|| Cursor on main panel.

Cursor on input box.

Cursor on electrons.

Cursor on the block.

|| The main panel consists of a circuit.

The circuit has a battery with a box to input the voltage.

Electrons represented as blue spheres are seen throughout the circuit.

A block of material is attached to the circuit at the bottom of the simulation.
|-
|| Cursor on left panel.

Point to the two bands.

Point to the lower band.

Point to the higher band.

Point to the gap.

|| The expanded rectangle is divided into two bands.

Low energy band is valence band and high energy band is conduction band.

The material conducts electricity when electrons are present in the conduction band.

The gap between the two bands is known as bandgap.

|-
||Point to the lower band.
||We can see that by default all electrons are in the low energy state.

|-
|| Cursor on '''Materials''' panel on the right.
Point one by one.

Cursor on shine the light checkbox.

|| On the right panel we can see the '''Materials''' section.

It has '''Metal, Plastic''' and '''Photoconductor''' radio buttons.

On the right panel the '''Shine the light''' option is available.

|-
|| Cursor on torch.

|| At the bottom, we have a torch to shine light.

|-
||

Click on up arrow on battery voltage box till 0.2 volts.

|| Let us leave the default selection of material as '''Metal'''.

Click the up arrow in the '''Battery Voltage''' box to increase the voltage to 0.2 volts.

|-
||Point to the circuit.
||Observe the movement of electrons in the circuit.

It means current is flowing through the circuit.
|-
||Point to the valence band in the left panel.
||Observe the movement of electrons in the valence band.

|-
|| Click on the Pause button.
|| Let us now pause the simulation.
|-
||

Point to the circuit.

Point to the circuit.
|| This simulation helps to understand the concept of conductivity.

Observe that electrons are present in the circuit, but are not moving.

|-
||Click the '''Play''' button at the bottom.
||Now click the '''Play''' button.

|-
||Only narration
||The electrons start moving, as we increase the voltage.

|-
|| Click the up arrow button of Battery Voltage to 2 V.
|| Let's increase the voltage to 2 volts and observe.

|-
||

Point to the circuit.

||As voltage increases the potential difference between the terminals increases.

The electrons now move faster and also move to higher energy levels.
|-
|| Only narration.
||This makes metals good conductors of electricity.
|-
|| Click on the '''Plastic''' radio button.

Point to band gap in the left panel.
|| Let us change the material to '''Plastic'''.

Observe that the energy gap between the two bands has increased.

|-
||Point to the circuit and to Voltage box: 2 V.
||We do not see the movement of electrons, even at high voltage.

|-
||Click the '''Shine The Light '''checkbox.

||Now let us click the '''Shine The Light '''checkbox.

Observe that even after shining light electrons are not moving.

|-
|| Cursor on left panel >> band gap.

|| The band gap for '''plastic''' is very high.

So current does not flow in the circuit even after shining the light.

Hence '''plastic''' is a non-conductor.
|-
|| Uncheck the '''Shine The Light''' check box.
|| Let us uncheck the '''Shine The Light''' check box.

|-
|| Click on the '''Photoconductor''' radio button.
|| Let us change the material to '''Photoconductor'''.

|-
||Point to Voltage box: 2 V.
||Even at high voltage no movement of electrons is seen.

|-
||Click the '''Shine The Light''' check box.

Point to the movement of electrons.

||Let us shine the light now.

We can now see the movement of electrons as light strikes the '''photoconductor'''.

|-
||Point to the electrons in the energy bands in the left panel.
||Observe that some electrons excite to the higher energy band.

|-
|| Cursor on Left panel.
|| Band gap for a '''photoconductor''' is less than '''plastic''' and more than metal.

Hence when light strikes the material it excites electrons to high energy levels.

|-
||Only narration
||This intermediate material is a semiconductor with a small band gap.

Semiconductors conduct electricity in the presence of light, heat and impurities.
|-
||
|| With this we come to the end of this tutorial.

Let's summarise.
|-
|| '''Slide Number 6'''

'''Summary'''
|| In this tutorial we have learnt how,

*Change in voltage makes the electrons move in the circuit.
*Large band gap in '''plastics''' do not allow conductivity.
*Shining light on a '''photoconductor''' causes it to conduct electricity.

|-
|| '''Slide Number 7'''

'''Assignment'''
| Here is an assignment for you.

Check if,
*The conductivity of a metal changes when light is shined.
*Photoconductors conduct electricity when battery voltage is decreased.

|-
|| '''Slide Number 8'''

'''About Spoken Tutorial Project '''
|| The video at the following link summarizes the Spoken Tutorial project.

Please download and watch it.
|-
|| '''Slide Number 9'''

'''Spoken tutorial workshops '''
|| We conduct workshops using spoken tutorials and give certificates.

For more details, please contact us.
|-
|| '''Slide Number 10'''

'''Answers for THIS Spoken Tutorial '''
|| Please post your timed queries in this forum.
|-
|| '''Slide Number 11'''

'''Acknowledgement '''
|| Spoken Tutorial project is funded by the Ministry of Education (MoE), Govt. of India
|-
||
|| This is Vidhi Thakur, a FOSSEE summer fellow 2022, IIT Bombay signing off.

Thank you for joining.

|-
|}

PhET-Simulations-for-Physics/C3/Semiconductors/English

2022-12-17T03:30:51Z

Vidhithakur:

'''Semiconductors'''

'''Author: Vidhi Thakur'''

'''Keywords: PhET simulation''', dopants, diode, valence band, conduction band, donor, acceptor, depletion region '''video tutorial.'''

{|border=1
|-
||'''Visual Cue'''
||''' Narration '''
|-
|| '''Slide Number 1'''

'''Title Slide'''
|| Welcome to this spoken tutorial on '''Semiconductors'''.
|-
|| '''Slide Number 2'''

'''Learning Objectives'''

|| In this tutorial, we will learn,

* How a battery acts as a driving force in a circuit.
* To add dopants to move the electrons in the circuit.
* How the dopants change energy levels in a semiconductor
* Why a pn junction acts as a diode
* Why a depletion region does not allow current to flow.

|-
|| '''Slide Number 3'''

'''System Requirement'''
|| Here I am using

*'''Windows 11 (64 bit)'''.

*'''Java Version 1.8'''.
|-
||'''Slide Number 4'''

'''Pre-requisites'''
'''https://spoken-tutorial.org'''
||To follow this tutorial the learner should be familiar with topics in high school science.
Please use the link below to access the tutorials on PhET simulations.
|-
||'''Slide Number 5'''

'''Link for PhET simulation'''

point to

'''https://phet.colorado.edu/en/simulations/conductivity/about'''
|| Please use the given link to download the PhET simulation.

'''https://phet.colorado.edu/en/simulations/semiconductor/about'''
|-
||'''Point to the file in the Downloads folder'''.
|| I have downloaded the '''Semiconductors simulation '''to my '''Downloads''' folder.
|-
||'''Double click the file to open'''
|| To open the simulation double click on the file.

|-
||'''Cursor on the interface.'''
|| This is the interface of '''Semiconductors simulation.'''
|-
||Cursor on '''main panel'''.

Cursor on '''input box.'''

Cursor on '''electrons.'''

|| The main panel consists of a circuit.

The circuit has a battery with the box to input the voltage.

'''Electrons''' are represented as blue spheres in the circuit.
|-
|| Cursor on '''dopants.'''

|| Point to the P Type and N Type dopants at the bottom.
A dopant is an impurity added to semiconductors to modify their conductivity.

At the bottom right P-type dopant is represented as '''red''' spheres and N-type as '''green''' spheres.

A P Type dopant is represented as '''red''' spheres and N Type as '''green''' spheres.

P-type dopant is with more holes, whereas n-type dopant is with more electrons.

|-
|| Cursor on '''dopant.'''

Cursor on '''valence band.'''
|| An electrode is connected to each dopant.

It expands into bands represented as '''yellow rectangles''' on the left panel.

The low energy band is the''' valence''' band.

It is filled with blue spheres as electrons and plus signs as holes.

|-
||

Cursor on '''conduction''' band.
|| The high energy band is the '''conduction''' band.

In semiconductors the gap between the bands is small.

'''Internal force '''arrow gives us the direction of the internal force.

'''Battery force '''arrow''' '''gives us the direction of battery force.
|-
|| Cursor on right panel.

Point to '''one(1) '''Segment.

'''Two(2)''' Segments.

|| On the right panel the '''Segments''' section is present.

It consists of one and two as options.

The''' one(1) '''Segment provides space for one dopant only.

The '''two(2)''' Segments provide space for two segments.

|-
|| Click on segment '''one'''.

Cursor on bands.

|| Let us first select segment one(1).

Here only one segment is present.

The electrode attached to the dopant expands into bands with electrons and holes.

Lower energy band is the valence band with low energy.

The higher energy band is the conduction band with high energy.

|-
|| Drag and add '''P-type''' in space in the bottom of the circuit.

Click on the up arrow till '''4V'''.

Cursor on circuit diagram.
|| Let’s drag and place a '''P-type '''dopant to fill in the purple space in the circuit.

Increase the voltage to '''4 volts''' and observe the movement of electrons in the circuit.

Current flows in the circuit with low energy from left-right.
|-
|| Click on down arrow till '''-4V.'''
|| Now let us decrease the voltage to''' -4 volts'''.

This way we change the terminals of the battery in the opposite direction.

There is a flow of current in the right-left direction in the circuit.

Changing the terminals, changes the direction of potential difference.

Hence direction of flow of current changes.

|-
|| Click on '''Clear Dopants'''.

Drag and add '''N-type''' dopant and click up arrow till 4V.

|| Let us clear dopants now.

Add N-type dopant to the space and increase the voltage to '''4 volts'''.

Since N-type dopants have more electrons they are known as '''donors'''.

The flow of current is from left to right in the conduction band at high energy.

|-
||

Click the down arrow till -4V.

||

Now let us change the voltage to''' -4 ''', that is. change the terminal of the battery.

This time flow of current is in the right-left''' '''direction

in the conduction band.

|-
|| Click on '''two''' segment.

Drag and add '''P-type''' dopant in the left space.

Click the arrow till 4V.

Cursor on internal force and battery force.
|| Now let us select Segments '''two(2)'''.

Drag and add '''P-type''' dopant in the left space and increase the voltage to 4 volts.

Note that electrons and holes in the valence band of the left segment disappear.

This is because p-type dopant is an acceptor.

Internal force is zero and battery force is from left to right.

So, there is no flow of current in the circuit.

|-
|| Drag and add an '''N-type''' dopant in the right space.

Cursor on battery.

|| Let us drag and add an N-type dopant in the right space.

Such diode formation is known as '''pn''' junction diode.

Here the positive terminal of the battery is connected to N-type.

Negative terminal is connected to the P-type.

Such arrangement is known as '''reversed bias.'''

|-
|| Cursor on valence band and conduction band.
|| Empty space is filled by electrons in the '''P-type''' dopant.

And holes occupy the conduction band of '''N-type''' dopant.

The direction of internal force, and battery force, are in the same''' '''direction.

Hence a more resistive thicker '''depletion''' region is formed.

This is due to the diffusion of carriers across the junction of the pn diode.

So, no flow of current is observed.

|-
|| Click on down arrow till '''-4V'''.

Cursor on battery and internal force.

Cursor on battery.
|| Now let us slowly change the voltage to '''-4 Volts'''.

Notice that decrease in voltage decreases the size of the battery force arrow.

At -4 Volts the battery force changes the direction and internal force becomes zero.

At -4 Volts, P-type dopant is connected to the positive terminal and vice-versa.

Hence it is '''forward biased''', so the depletion region is thinner here.

So, current flow is seen from N-type to P-type '''dopant '''in''' '''right-left direction.

|-
|| Click on '''Clear Dopants'''.

Drag and add '''N-type''' dopant in left space and click up arrow till 4V.

Cursor on battery and internal force.
|| Now let”s clear the '''dopants'''.

Drag and add '''N-type''' dopant in the left space and increase the voltage to '''4 Volts'''.

Electrons and holes are visible in the left segment as N-type dopants are donors.

'''Internal''' '''force''' is zero and battery force is in the right direction.

So, there is no flow of current,''' '''

|-
|| Drag and add a P-type dopant in the right space.

Cursor on battery

|| Let us drag and add '''P-type '''dopant in the right segment.

Such diode formation is known as '''pn junction diode'''.

Here, positive terminal is connected to P-type and negative terminal to N-type.

Such an arrangement is known as''' forward bias.'''

Flow of current is seen from N-type to P-type dopant from left to right direction.

Battery force is also in the same direction.
|-
|| Click on down arrow till '''-4V'''.

|| I will now change the voltage to''' -4 Volts'''.

The electrons in the left segment of the conduction band disappear.

Only holes are left.

Internal force and battery force are in the left direction.

So, we see no flow of current.

|-
|| '''Slide Number 6'''

'''Summary'''
|| With this we come to the end of this tutorial.

Let's summarise.

In this tutorial we have learnt,* How a battery acts as a driving force in a circuit.
* To add dopants to move the electrons in the circuit.
* How the dopants change energy levels in a semiconductor
* Why a pn junction acts as a diode
* Why a depletion region does not allow current to flow.

|-
|| '''Slide Number 7'''

'''Assignment'''
||

As an assignment,

Make various combinations of dopants at different voltages and record the observations.

|-
|| '''Slide Number 8'''

'''About Spoken Tutorial Project '''
||The video at the following link summarizes the Spoken Tutorial project.
* Please download and watch it.

|-
|| '''Slide Number 9'''

'''Spoken tutorial workshops '''
||We conduct workshops using spoken tutorials and give certificates.
* For more details, please contact us.

|-
|| '''Slide Number 10'''

'''Answers for THIS Spoken Tutorial '''

Do you have questions in THIS Spoken Tutorial?

Please visit this site

Choose the minute and second where you have the question.

Explain your question briefly

The spoken tutorial project will ensure answer.

You will have to register on this website to ask questions.
|| * <div style="margin-left:1.245cm;margin-right:0cm;">Please post your timed queries in this forum.

|-
|| '''Slide Number 11'''

'''Forum '''
||The Spoken Tutorial forum is for specific questions on this tutorial.
* Please do not post unrelated and general questions on them.
* This will help reduce the clutter.
* With less clutter, we can use these discussions as instructional material.

|-
|| '''Slide Number 12'''

'''Acknowledgement '''
|| Spoken Tutorial project is funded by the Ministry of Education (MoE), Govt. of India
|-
||
||This is Vidhi Thakur, a FOSSEE
* summer fellow 2022, IIT Bombay
* signing off

Thank you for joining.
|-
|}

<div style="margin-left:0.811cm;margin-right:0cm;">

PhET-Simulations-for-Physics/C3/Semiconductors/English

2022-12-17T03:27:59Z

Vidhithakur:

'''Semiconductors'''

'''Author: Vidhi Thakur'''

'''Keywords: PhET simulation''', dopants, diode, valence band, conduction band, donor, acceptor, depletion region '''video tutorial.'''

{|border=1
|-
||'''Visual Cue'''
||''' Narration '''
|-
|| '''Slide Number 1'''

'''Title Slide'''
|| Welcome to this spoken tutorial on '''Semiconductors'''.
|-
|| '''Slide Number 2'''

'''Learning Objectives'''

|| In this tutorial, we will learn,

* How a battery acts as a driving force in a circuit.
* To add dopants to move the electrons in the circuit.
* How the dopants change energy levels in a semiconductor
* Why a pn junction acts as a diode
* Why a depletion region does not allow current to flow.

|-
|| '''Slide Number 3'''

'''System Requirement'''
|| Here I am using

*'''Windows 11 (64 bit)'''.

*'''Java Version 1.8'''.
|-
||'''Slide Number 4'''

'''Pre-requisites'''
'''https://spoken-tutorial.org'''
||To follow this tutorial the learner should be familiar with topics in high school science.
Please use the link below to access the tutorials on PhET simulations.
|-
||'''Slide Number 5'''

'''Link for PhET simulation'''

point to

'''https://phet.colorado.edu/en/simulations/conductivity/about'''
|| Please use the given link to download the PhET simulation.

'''https://phet.colorado.edu/en/simulations/semiconductor/about'''
|-
||'''Point to the file in the Downloads folder'''.
|| I have downloaded the '''Semiconductors simulation '''to my '''Downloads''' folder.
|-
||'''Double click the file to open'''
|| To open the simulation double click on the file.

|-
||'''Cursor on the interface.'''
|| This is the interface of '''Semiconductors simulation.'''
|-
||Cursor on '''main panel'''.

Cursor on '''input box.'''

Cursor on '''electrons.'''

|| The main panel consists of a circuit.

The circuit has a battery with the box to input the voltage.

'''Electrons''' are represented as blue spheres in the circuit.
|-
|| Cursor on '''dopants.'''

|| Point to the P Type and N Type dopants at the bottom.
A dopant is an impurity added to semiconductors to modify their conductivity.

At the bottom right P-type dopant is represented as '''red''' spheres and N-type as '''green''' spheres.

A P Type dopant is represented as '''red''' spheres and N Type as '''green''' spheres.

P-type dopant is with more holes, whereas n-type dopant is with more electrons.

|-
|| Cursor on '''dopant.'''

Cursor on '''valence band.'''
|| An electrode is connected to each dopant.

It expands into bands represented as '''yellow rectangles''' on the left panel.

The low energy band is the''' valence''' band.

It is filled with blue spheres as electrons and plus signs as holes.

|-
||

Cursor on '''conduction''' band.
|| The high energy band is the '''conduction''' band.

In semiconductors the gap between the bands is small.

'''Internal force '''arrow gives us the direction of the internal force.

'''Battery force '''arrow''' '''gives us the direction of battery force.
|-
|| Cursor on right panel.

Point to '''one(1) '''Segment.

'''Two(2)''' Segments.

|| On the right panel the '''Segments''' section is present.

It consists of one and two as options.

The''' one(1) '''Segment provides space for one dopant only.

The '''two(2)''' Segments provide space for two segments.

|-
|| Click on segment '''one'''.

Cursor on bands.

|| Let us first select segment one(1).

Here only one segment is present.

The electrode attached to the dopant expands into bands with electrons and holes.

Lower energy band is the valence band with low energy.

The higher energy band is the conduction band with high energy.

|-
|| Drag and add '''P-type''' in space in the bottom of the circuit.

Click on the up arrow till '''4V'''.

Cursor on circuit diagram.
|| Let’s drag and place a '''P-type '''dopant to fill in the purple space in the circuit.

Increase the voltage to '''4 volts''' and observe the movement of electrons in the circuit.

Current flows in the circuit with low energy from left-right.
|-
|| Click on down arrow till '''-4V.'''
|| Now let us decrease the voltage to''' -4 volts'''.

This way we change the terminals of the battery in the opposite direction.

There is a flow of current in the right-left direction in the circuit.

Changing the terminals, changes the direction of potential difference.

Hence direction of flow of current changes.

|-
|| Click on '''Clear Dopants'''.

Drag and add '''N-type''' dopant and click up arrow till 4V.

|| Let us clear dopants now.

Add N-type dopant to the space and increase the voltage to '''4 volts'''.

Since N-type dopants have more electrons they are known as '''donors'''.

The flow of current is from left to right in the conduction band at high energy.

|-
||

Click the down arrow till -4V.

||

Now let us change the voltage to''' -4 ''', that is. change the terminal of the battery.

This time flow of current is in the right-left''' '''direction

in the conduction band.

|-
|| Click on '''two''' segment.

Drag and add '''P-type''' dopant in the left space.

Click the arrow till 4V.

Cursor on internal force and battery force.
|| Now let us select Segments '''two(2)'''.

Drag and add '''P-type''' dopant in the left space and increase the voltage to 4 volts.

Note that electrons and holes in the valence band of the left segment disappear.

This is because p-type dopant is an acceptor.

Internal force is zero and battery force is from left to right.

So, there is no flow of current in the circuit.

|-
|| Drag and add an '''N-type''' dopant in the right space.

Cursor on battery.

|| Let us drag and add an N-type dopant in the right space.

Such diode formation is known as '''pn''' junction diode.

Here the positive terminal of the battery is connected to N-type.

Negative terminal is connected to the P-type.

Such arrangement is known as '''reversed bias.'''

|-
|| Cursor on valence band and conduction band.
|| Empty space is filled by electrons in the '''P-type''' dopant.

And holes occupy the conduction band of '''N-type''' dopant.

The direction of internal force, and battery force, are in the same''' '''direction.

Hence a more resistive thicker '''depletion''' region is formed.

This is due to the diffusion of carriers across the junction of the pn diode.

So, no flow of current is observed.

|-
|| Click on down arrow till '''-4V'''.

Cursor on battery and internal force.

Cursor on battery.
|| Now let us slowly change the voltage to '''-4 Volts'''.

Notice that decrease in voltage decreases the size of the battery force arrow.

At -4 Volts the battery force changes the direction and internal force becomes zero.

At -4 Volts, P-type dopant is connected to the positive terminal and vice-versa.

Hence it is '''forward biased''', so the depletion region is thinner here.

So, current flow is seen from N-type to P-type '''dopant '''in''' '''right-left direction.

|-
|| Click on '''Clear Dopants'''.

Drag and add '''N-type''' dopant in left space and click up arrow till 4V.

Cursor on battery and internal force.
|| Now let”s clear the '''dopants'''.

Drag and add '''N-type''' dopant in the left space and increase the voltage to '''4 Volts'''.

Electrons and holes are visible in the left segment as N-type dopants are donors.

'''Internal''' '''force''' is zero and battery force is in the right direction.

So, there is no flow of current,''' '''

|-
|| Drag and add a P-type dopant in the right space.

Cursor on battery

|| Let us drag and add '''P-type '''dopant in the right segment.

Such diode formation is known as '''pn junction diode'''.

Here, positive terminal is connected to P-type and negative terminal to N-type.

Such an arrangement is known as''' forward bias.'''

Flow of current is seen from N-type to P-type dopant from left to right direction.

Battery force is also in the same direction.
|-
|| Click on down arrow till '''-4V'''.

|| I will now change the voltage to''' -4 Volts'''.

The electrons in the left segment of the conduction band disappear.

Only holes are left.

Internal force and battery force are in the left direction.

So, we see no flow of current.

|-
|| '''Slide Number 6'''

'''Summary'''
|| With this we come to the end of this tutorial.

Let's summarise.

In this tutorial we have learnt,* How a battery acts as a driving force in a circuit.
* To add dopants to move the electrons in the circuit.
* How the dopants change energy levels in a semiconductor
* Why a pn junction acts as a diode
* Why a depletion region does not allow current to flow.

|-
|| '''Slide Number 7'''

'''Assignment'''
||

As an assignment,

Make various combinations of dopants at different voltages and record the observations.

|-
|| '''Slide''': 8

'''About Spoken Tutorial Project '''
||The video at the following link summarizes the Spoken Tutorial project.
* Please download and watch it.

|-
|| '''Slide''': 9

'''Spoken tutorial workshops '''
||We conduct workshops using spoken tutorials and give certificates.
* For more details, please contact us.

|-
|| '''Slide''': 10

'''Answers for THIS Spoken Tutorial '''

Do you have questions in THIS Spoken Tutorial?

Please visit this site

Choose the minute and second where you have the question.

Explain your question briefly

The spoken tutorial project will ensure answer.

You will have to register on this website to ask questions.
|| * <div style="margin-left:1.245cm;margin-right:0cm;">Please post your timed queries in this forum.

|-
|| '''Slide''': 11

'''Forum '''
||The Spoken Tutorial forum is for specific questions on this tutorial.
* Please do not post unrelated and general questions on them.
* This will help reduce the clutter.
* With less clutter, we can use these discussions as instructional material.

|-
|| '''Slide''': 12

'''Acknowledgement '''
|| Spoken Tutorial project is funded by the Ministry of Education (MoE), Govt. of India
|-
||
||This is Vidhi Thakur, a FOSSEE
* summer fellow 2022, IIT Bombay
* signing off

Thank you for joining.
|-
|}

<div style="margin-left:0.811cm;margin-right:0cm;">

PhET-Simulations-for-Physics/C3/Semiconductors/English

2022-12-17T03:21:07Z

Vidhithakur: Created page with "'''Semiconductors''' '''Author: Vidhi Thakur''' '''Keywords: PhET simulation''', dopants, diode, valence band, conduction band, donor, acceptor, depletion region '''video..."

'''Semiconductors'''

'''Author: Vidhi Thakur'''

'''Keywords: PhET simulation''', dopants, diode, valence band, conduction band, donor, acceptor, depletion region '''video tutorial.'''

{|border=1
|-
||'''Visual Cue'''
||''' Narration '''
|-
|| '''Slide Number 1'''

'''Title Slide'''
|| Welcome to this spoken tutorial on '''Semiconductors'''.
|-
|| '''Slide Number 2'''

'''Learning Objectives'''

|| In this tutorial, we will learn,

* How a battery acts as a driving force in a circuit.
* To add dopants to move the electrons in the circuit.
* How the dopants change energy levels in a semiconductor
* Why a pn junction acts as a diode
* Why a depletion region does not allow current to flow.

|-
|| '''Slide Number 3'''

'''System Requirement'''
|| Here I am using

'''Windows 11 (64 bit).'''

'''Java Version 1.8'''
|-
||'''Slide Number 4'''

'''Pre-requisites'''
'''https://spoken-tutorial.org'''
||To follow this tutorial the learner should be familiar with topics in high school science.
Please use the link below to access the tutorials on PhET simulations.
|-
||'''Slide Number 5'''

'''Link for PhET simulation'''

point to

'''https://phet.colorado.edu/en/simulations/conductivity/about'''
|| Please use the given link to download the PhET simulation.

'''https://phet.colorado.edu/en/simulations/semiconductor/about'''
|-
||'''Point to the file in the Downloads folder'''.
|| I have downloaded the '''Semiconductors simulation '''to my '''Downloads''' folder.
|-
||'''Double click the file to open'''
|| To open the simulation double click on the file.

|-
||'''Cursor on the interface.'''
|| This is the interface of '''Semiconductors simulation.'''
|-
||Cursor on '''main panel'''.

Cursor on '''input box.'''

Cursor on '''electrons.'''

|| The main panel consists of a circuit.

The circuit has a battery with the box to input the voltage.

'''Electrons''' are represented as blue spheres in the circuit.
|-
|| Cursor on '''dopants.'''

|| Point to the P Type and N Type dopants at the bottom.
A dopant is an impurity added to semiconductors to modify their conductivity.

At the bottom right P-type dopant is represented as '''red''' spheres and N-type as '''green''' spheres.

A P Type dopant is represented as '''red''' spheres and N Type as '''green''' spheres.

P-type dopant is with more holes, whereas n-type dopant is with more electrons.

|-
|| Cursor on '''dopant.'''

Cursor on '''valence band.'''
|| An electrode is connected to each dopant.

It expands into bands represented as '''yellow rectangles''' on the left panel.

The low energy band is the''' valence''' band.

It is filled with blue spheres as electrons and plus signs as holes.

|-
||

Cursor on '''conduction''' band.
|| The high energy band is the '''conduction''' band.

In semiconductors the gap between the bands is small.

'''Internal force '''arrow gives us the direction of the internal force.

'''Battery force '''arrow''' '''gives us the direction of battery force.
|-
|| Cursor on right panel.

Point to '''one(1) '''Segment.

'''Two(2)''' Segments.

|| On the right panel the '''Segments''' section is present.

It consists of one and two as options.

The''' one(1) '''Segment provides space for one dopant only.

The '''two(2)''' Segments provide space for two segments.

|-
|| Click on segment '''one'''.

Cursor on bands.

|| Let us first select segment one(1).

Here only one segment is present.

The electrode attached to the dopant expands into bands with electrons and holes.

Lower energy band is the valence band with low energy.

The higher energy band is the conduction band with high energy.

|-
|| Drag and add '''P-type''' in space in the bottom of the circuit.

Click on the up arrow till '''4V'''.

Cursor on circuit diagram.
|| Let’s drag and place a '''P-type '''dopant to fill in the purple space in the circuit.

Increase the voltage to '''4 volts''' and observe the movement of electrons in the circuit.

Current flows in the circuit with low energy from left-right.
|-
|| Click on down arrow till '''-4V.'''
|| Now let us decrease the voltage to''' -4 volts'''.

This way we change the terminals of the battery in the opposite direction.

There is a flow of current in the right-left direction in the circuit.

Changing the terminals, changes the direction of potential difference.

Hence direction of flow of current changes.

|-
|| Click on '''Clear Dopants'''.

Drag and add '''N-type''' dopant and click up arrow till 4V.

|| Let us clear dopants now.

Add N-type dopant to the space and increase the voltage to '''4 volts'''.

Since N-type dopants have more electrons they are known as '''donors'''.

The flow of current is from left to right in the conduction band at high energy.

|-
||

Click the down arrow till -4V.

||

Now let us change the voltage to''' -4 ''', that is. change the terminal of the battery.

This time flow of current is in the right-left''' '''direction

in the conduction band.

|-
|| Click on '''two''' segment.

Drag and add '''P-type''' dopant in the left space.

Click the arrow till 4V.

Cursor on internal force and battery force.
|| Now let us select Segments '''two(2)'''.

Drag and add '''P-type''' dopant in the left space and increase the voltage to 4 volts.

Note that electrons and holes in the valence band of the left segment disappear.

This is because p-type dopant is an acceptor.

Internal force is zero and battery force is from left to right.

So, there is no flow of current in the circuit.

|-
|| Drag and add an '''N-type''' dopant in the right space.

Cursor on battery.

|| Let us drag and add an N-type dopant in the right space.

Such diode formation is known as '''pn''' junction diode.

Here the positive terminal of the battery is connected to N-type.

Negative terminal is connected to the P-type.

Such arrangement is known as '''reversed bias.'''

|-
|| Cursor on valence band and conduction band.
|| Empty space is filled by electrons in the '''P-type''' dopant.

And holes occupy the conduction band of '''N-type''' dopant.

The direction of internal force, and battery force, are in the same''' '''direction.

Hence a more resistive thicker '''depletion''' region is formed.

This is due to the diffusion of carriers across the junction of the pn diode.

So, no flow of current is observed.

|-
|| Click on down arrow till '''-4V'''.

Cursor on battery and internal force.

Cursor on battery.
|| Now let us slowly change the voltage to '''-4 Volts'''.

Notice that decrease in voltage decreases the size of the battery force arrow.

At -4 Volts the battery force changes the direction and internal force becomes zero.

At -4 Volts, P-type dopant is connected to the positive terminal and vice-versa.

Hence it is '''forward biased''', so the depletion region is thinner here.

So, current flow is seen from N-type to P-type '''dopant '''in''' '''right-left direction.

|-
|| Click on '''Clear Dopants'''.

Drag and add '''N-type''' dopant in left space and click up arrow till 4V.

Cursor on battery and internal force.
|| Now let”s clear the '''dopants'''.

Drag and add '''N-type''' dopant in the left space and increase the voltage to '''4 Volts'''.

Electrons and holes are visible in the left segment as N-type dopants are donors.

'''Internal''' '''force''' is zero and battery force is in the right direction.

So, there is no flow of current,''' '''

|-
|| Drag and add a P-type dopant in the right space.

Cursor on battery

|| Let us drag and add '''P-type '''dopant in the right segment.

Such diode formation is known as '''pn junction diode'''.

Here, positive terminal is connected to P-type and negative terminal to N-type.

Such an arrangement is known as''' forward bias.'''

Flow of current is seen from N-type to P-type dopant from left to right direction.

Battery force is also in the same direction.
|-
|| Click on down arrow till '''-4V'''.

|| I will now change the voltage to''' -4 Volts'''.

The electrons in the left segment of the conduction band disappear.

Only holes are left.

Internal force and battery force are in the left direction.

So, we see no flow of current.

|-
|| '''Slide Number 11'''

'''Summary'''
|| With this we come to the end of this tutorial.

Let's summarise.

In this tutorial we have learnt,* How a battery acts as a driving force in a circuit.
* To add dopants to move the electrons in the circuit.
* How the dopants change energy levels in a semiconductor
* Why a pn junction acts as a diode
* Why a depletion region does not allow current to flow.

|-
|| '''Slide Number 12'''

'''Assignment'''
||

As an assignment,

Make various combinations of dopants at different voltages and record the observations.

|-
|| '''Slide''': 13

'''About Spoken Tutorial Project '''
||The video at the following link summarizes the Spoken Tutorial project.
* Please download and watch it.

|-
|| '''Slide''': 14

'''Spoken tutorial workshops '''
||We conduct workshops using spoken tutorials and give certificates.
* For more details, please contact us.

|-
|| '''Slide''': 15

'''Answers for THIS Spoken Tutorial '''

Do you have questions in THIS Spoken Tutorial?

Please visit this site

Choose the minute and second where you have the question.

Explain your question briefly

The spoken tutorial project will ensure answer.

You will have to register on this website to ask questions.
|| * <div style="margin-left:1.245cm;margin-right:0cm;">Please post your timed queries in this forum.

|-
|| '''Slide''': 17

'''Forum '''
||The Spoken Tutorial forum is for specific questions on this tutorial.
* Please do not post unrelated and general questions on them.
* This will help reduce the clutter.
* With less clutter, we can use these discussions as instructional material.

|-
|| '''Slide''': 16

'''Acknowledgement '''
|| Spoken Tutorial project is funded by the Ministry of Education (MoE), Govt. of India
|-
||
||This is Vidhi Thakur, a FOSSEE
* summer fellow 2022, IIT Bombay
* signing off

Thank you for joining.
|-
|}

<div style="margin-left:0.811cm;margin-right:0cm;">

PhET-Simulations-for-Chemistry/C3/Sugar-and-Salt-solutions/English

2022-11-17T06:35:46Z

Vidhithakur:

'''Sugar and Salt Solutions'''

'''Author: Vidhi Thakur'''

'''Keywords: '''PhET simulation''', '''Sugar, Salts, solute, molarity, concentration, evaporation, Conductivity, water partial charges, space fill format and Ball and stick format, spoken tutorial, video tutorial.

{|border=1
|-
||'''Visual Cue'''
||'''Narration'''
|-
|| '''Slide Number 1'''

'''Title Slide'''
|| Welcome to this tutorial on '''Sugar and Salt solutions.'''
|-
|| '''Slide Number 2'''

'''Learning Objectives'''

|| In this tutorial, we will learn about,

Change in concentration of the solution on:
*addition of a solute
*addition of a solvent
*evaporation

Conductivity of a solution

Identify whether the given compound is ionic or covalent.
|-
|| '''Slide Number 3'''

'''System Requirement'''
|| Here I am using

'''Windows 11 (64 bit).'''

'''Java version 1.8'''

|-
||'''Slide Number 4'''

'''Pre-requisites'''
'''[https://spoken-tutorial.org/ https://spoken-tutorial.org]'''

||To follow this tutorial, learner should be familiar with topics in high school science.

Please use the link below to access the tutorials on PhET Simulations.

|-
||'''Slide Number 5'''

'''Link for PhET simulation'''

point to

'''https://phet.colorado.edu/en/simulations/sugar-and-salt-solutions'''

||Please use the given link to download the PhET simulation.

|-
||'''Point to the file in the Downloads folder'''.
||I have downloaded '''Sugar and Salt Solutions''' simulation, to my '''Downloads''' folder.
|-
||'''Double click the file to open'''
||To open the simulation double click on the file.
|-
||'''Cursor on the interface.'''
||This is the interface of '''Sugar and Salt Solutions simulation'''
|-
|| Cursor on simulation interface.

Move the cursor on the tabs, '''Macro, Micro and Water'''.

|| The simulation interface has 3 tabs.

'''Macro, Micro '''and''' Water'''.
|-
|| Cursor on Macro interface.

|| '''Macro '''tab opens first by default.

The main panel shows a container with inlet and outlet water faucets.
|-
|| Show the location of inlet and outlet Faucets.
|| Inlet water faucet is placed at the top-left of the container.

Outlet water faucet is placed at the bottom-right of the container.
|-
|| Cursor on the container.
|| The container is graduated and filled with water.

The markings show 0 Litre, 1 Litre and 2 Litres.
|-
|| Show salt shaker.
|| A salt shaker is placed at the top of the container.

Shake the salt dispenser to add salt to the container.
|-
|| Cursor on the right panel.
|| On the right, we see '''Solute''', '''Concentration '''and''' Conductivity '''panels.
|-
|| Cursor on the right panel.

Point to the options.
|| From the '''Solute''' panel, the solute type can be selected.

The '''Solute''' panel shows '''Salt''' and '''Sugar''' radio buttons.

From here we can select the solute type.

Let us keep the default solute as salt.

|-
|| Cursor on the right panel.

Click on the show values checkbox
|| The '''Concentration''' panel shows the concentration as a bar graph.

Let us check the '''Show values''' checkbox to see the concentration values.
|-
|| Cursor to bottom panel

Drag the Evaporation slider from none to lots.
|| At the bottom we see '''Evaporation''' panel with a slider.

To evaporate water, drag the slider from '''none''' to '''lots'''.

Observe the change in the concentration in the '''Concentration''' panel.

As water evaporates the concentration of the salt increases.

|-
|| Cursor to the bottom of container
|| There is a '''Remove salt '''button at the bottom of the container.

On clicking this button salt is removed from the solution.
|-
|| Click the '''Reset All '''button.
|| '''Reset All '''button resets the simulation to default parameters.
|-
|| Cursor on the water container.

Click on the show value check box.
|| Let us observe the concentration of salt in water.

Let the water level in the container be at 1 litre mark.

Let us check the '''Show values''' box.
|-
|| Shake the salt dispenser.
|| Shake the salt shaker to add salt to the container.

|-
|| '''Slide Number 6'''

'''Definition of concentration'''

||

Concentration is a measure of the amount of solute dissolved in a given solution.

Molarity is one way of expressing concentration.

Molarity = Number of moles of the solute/Volume of the solution in litres(L)

Molarity (M) = n/Vyes after recording the concentration as a slide with table The show values values check box shows various values of molarity.

Using the molarity we can calculate the amount of salt added.

We can show a table here with different molarities and the respective weights.

|-
|| Cursor on concentration panel

Shake the dispenser to add salt
|| On adding salt, concentration increases as seen in the concentration panel.

I will record the change in concentration.
|-
|| '''Slide Number 7'''

'''Calculations'''
|| Solute in the shaker is 100 g

Molecular weight of sodium chloride(NaCl) is 58.44 g/mol

Molarity = Weight /(Molecular wt x V)

Molarity = 100 / (58.44 x 1)

Molarity <nowiki>= 1.72 M(molar)</nowiki>

|-
|| Cursor on concentration panel
|| Let us add more salt and record the change in concentration.

Let's tabulate the values to calculate the amount of solute.
|-
|| '''Slide Number 8'''

'''Table 1'''
|| Here I have calculated the amount of solute for different concentrations.

|-
||Drag the slider on the inlet Faucet.
||Let's add some water to the container till the 1.5 litres mark.

Observe the concentration in the panel.
|-
||Cursor on the simulation.
||A decrease in concentration is observed.

As per the formula concentration is inversely related to the volume of solution.

Hence on increasing the volume, concentration decreases.
|-
|| Cursor on Evaporation panel.

Slide the evaporation slider to the right.

Cursor to the concentration panel.
|| Now let us see the effect of '''evaporation''' on concentration.

I will drag the evaporation slider from '''none ''' to ''' lots '''to decrease the volume.

We can see an increase in concentration as the volume decreases.
|-
|| Cursor to the green electrode

Cursor to red electrode

Cursor to bulb and battery
|| Let us now check the '''Conductivity''' panel.

It has a circuit with a green negatively charged anode.

The red positively charged electrode acts as a cathode.

A bulb is connected to a battery to observe the luminescence conductivity.
|-
|| Cursor on the right panel.

Drag the circuit inside the solution

Cursor towards the blub
|| Now let us observe the conductivity of the solution.

Let us drag the circuit inside the solution.

The bulb glows now.
|-
|| Shake the salt dispenser.

Cursor to the bulb

|| Let's add more salt to the container.

The bulb glows brighter as the concentration of salt in the solution increases.

|-
|| Point to the bulb.
|| Dissociated salts conduct electricity through ions.

Hence intensity of brightness increases.
|-
|| Click on Reset all button

Click on the show values checkbox
||Click on the '''Reset All ''' button.

Let us select the '''Show values''' checkbox in the Concentration panel.
|-
|| Cursor on the water container.

|| Let us observe the concentration of sugar in water.

Click on the '''Sugar '''radio button to select sugar as solute.
|-
|| Shake the sugar dispenser.
|| Let's add sugar to the container.

|-
|| Cursor on concentration panel

Shake the dispenser to add salt
|| On adding sugar concentration increases as seen in the Concentration panel.

Let's add more sugar to the container and record the concentration.

Let's tabulate the results.
|-
|| '''Slide Number 9'''

'''Table 2'''
|| Molecular weight of sugar is 342.3 g/mol

Here I have calculated the amount of sugar for different concentrations.
|-
|| Cursor on right panel.

Drag the circuit inside the solution

Cursor towards the blub
|| Let us observe the conductivity of sugar solution.

Drag and place the circuit inside the solution.

This time the bulb does not glow.
|-
|| Point to the solution and bulb.

|| This is because sugar does not dissociate into ions.

Hence cannot conduct electricity.

|-
|| Click on the micro tab to open.
|| To observe this phenomenon in detail click the '''Micro '''tab to open it.
|-
|| Cursor on the interface.
|| In the '''Micro''' tab, molecular movement of ions can be observed in the solution.
|-
|| Cursor on right panel.

|| On the right, you will see '''Solute '''and '''Concentration '''panels.

The '''Solute '''panel shows different solutes.

Let us look at the '''Concentration''' panel.

Here sodium ion is shown as a purple sphere and chloride ion as green sphere.

'''Sucrose''' is represented as a molecule with white, grey and red spheres.
|-
|| Cursor on the water container.

Cursor on pause and slow button

|| I will keep Sodium chloride as the default solute.

On the bottom left '''pause''' and '''slow-motion''' buttons can be seen.

Slow-motion button can be used to observe the dissociation in slow motion.
|-
|| Shake salt shaker in a container,

Click on the pause button.

Click the slow-motion button multiple times.

Cursor in right panel
|| Let us add sodium chloride to the container using the salt shaker.

Click the '''pause''' button as soon as the molecules touch the surface of water.

Now click the '''slow-motion''' button multiple times to observe slow dissociation.

I will continue to click the button until all the atoms ionize.

On adding the salt to water it dissociates into ions of opposite charges.

Observe the increase in concentration of the ions in the right panel.
|-
|| Cursor on the right panel.

Click on the Sucrose option in the solute panel.

Add Sucrose to the container.

Cursor towards the container.
|| Let's click the '''Reset All''' button to reset the simulation to default parameters.

Now I will change the solute to '''Sucrose'''.

Let's add '''Sucrose''' to the container.

As observed, '''Sucrose ''' does not dissociate into ions.
|-
|| Point to the molecules in the container.
|| Sucrose will not dissociate, as it is a molecular solid with covalent bonding.

So it will not show conductivity as shown by salts.

This explains the conductivity of salts but not sugar.
|-
|| Click the arrow button to show the solutes.
|| Now slide the '''solute''' panel to explore more solutes.

You can practise with the other solutes present in the panel.

|-
|| Cursor on Periodic table button.

Click on the button.

Close the periodic table box.
|| The''' Periodic table button''' is present in the right panel.

This gives information about the elements present in the selected molecule.

They can be individually identified as metals or non-metals.

Close the periodic table box.
|-
|| Click on the Water tab.

Cursor on magnified view.
|| Now click on the '''Water''' tab.

It shows a magnified version of molecular interactions between water molecules.

|-
|| Point to sugar and salt in molecular form.
|| Interface shows salt and sugar as solutes in molecular form.
|-
|| Cursor on the right panel.

Cursor on options and buttons.

Point to sugar highlight option.

Point to the sugar molecules in the Sugar bucket.

Uncheck the '''Sugar highlight '''option.

Point to the sugar molecules in the Sugar bucket.

Click the '''Water partial charges''' option.

Cursor on water partial charges in the container.
|| On the bottom right panel, you will see the '''Show '''panel.

It has two options, Water partial charges and Sugar highlight .

Sugar highlight option is selected by default.

Here the sugar molecules are highlighted in yellow colour.

Lets uncheck the '''Sugar highlight '''option.

Observe that sugar molecules appear in their default colours.

Click the '''Water partial charges''' option.

Partial charges are shown on all water molecules.

|-
|| Cursor on the button.

Click on the '''Sugar in 3D '''button.

Point to the model in the window.

Click on the Ball and stick model.
|| In the right panel, we can also see a '''Sugar in 3D '''button.

Now I will click the '''Sugar in 3D''' button.

A window opens with a 3D model of sugar in '''space fill''' format.

Now Let's select the Ball and stick option.

The sticks in the model represent covalent bonds between adjacent atoms.
|-
|| Click on the X button to close.
|| Let us close the window.
|-
|| Add salt and pause the simulation.

Cursor on the magnified view.

Cursor on negatively charged charges.

Cursor on positively charged charges.

|| Now let's add salt to water and immediately pause the simulation.

Observe the orientation of water's partial charges with sodium and chloride ions.

Negative partial charges coloured red are aligned around sodium ions.

Positive charges coloured white are aligned around chloride ions.

This demonstrates the dissociation at molecular level in the water.
|-
||Click on the '''Reset All'''.

Click on the water partial charges option.
||Click on the '''Reset All '''button on the right panel.

Select the water partial charges option in the '''Show''' panel.
|-
|| Add sugar to water and pause the simulation.

Cursor on magnified view.
|| Now add sugar to water and immediately pause the simulation.

This time the molecules are not aligned nor do they dissociate.

This is because sugar is a complex molecule with covalent bonds.

This resists its dissociation in water so no ions are formed.
|-
|| '''Slide Number 7'''

'''Summary'''
|| With this we come to the end of this tutorial.

Let's summarise.

In this tutorial we have learnt about,

Change in concentration of the solution on:
*addition of a solute
*addition of a solvent
*evaporation

Conductivity of a solution.

Identify whether the given compound is ionic or covalent.
|-
|| '''Slide Number 10'''

'''Assignment'''
||

As an assignment,

Explore more solutes and observe their dissociation in water.

Interpret the possible dissociated ions and predict their conductivity.
|-
|| '''Slide Number 11'''

'''About Spoken Tutorial Project '''
||The video at the following link summarizes the Spoken Tutorial project.
*Please download and watch it.

|-
|| '''Slide Number 12'''

'''Spoken tutorial workshops '''
||We conduct workshops using spoken tutorials and give certificates.
*For more details, please contact us.

|-
|| '''Slide Number 13'''

'''Answers for THIS Spoken Tutorial '''

Do you have questions in THIS Spoken Tutorial?

Please visit this site

Choose the minute and second where you have the question.

Explain your question briefly

The spoken tutorial project will ensure answer.

You will have to register on this website to ask questions.
|| * <div style="margin-left:1.245cm;margin-right:0cm;">Please post your timed queries in this forum.

|-
|| '''Slide Number 14'''

'''Forum '''
||The Spoken Tutorial forum is for specific questions on this tutorial.
*Please do not post unrelated and general questions on them.
*This will help reduce the clutter.
*With less clutter, we can use these discussions as instructional material.

|-
|| '''Slide Number 15'''

'''Acknowledgement '''
|| Spoken Tutorial project is funded by the Ministry of Education (MoE), Govt. of India
|-
||
||This is Vidhi Thakur, a FOSSEE
*summer fellow 2022, IIT Bombay
*signing off

Thank you for joining.

|-
|}

PhET-Simulations-for-Chemistry/C3/Sugar-and-Salt-solutions/English

2022-11-17T06:31:33Z

Vidhithakur:

'''Sugar and Salt Solutions'''

'''Author: Vidhi Thakur'''

'''Keywords: '''PhET simulation''', '''Sugar, Salts, solute, molarity, concentration, evaporation, Conductivity, water partial charges, space fill format and Ball and stick format, spoken tutorial, video tutorial.

{|border=1
|-
||'''Visual Cue'''
||'''Narration'''
|-
|| '''Slide Number 1'''

'''Title Slide'''
|| Welcome to this tutorial on '''Sugar and Salt solutions.'''
|-
|| '''Slide Number 2'''

'''Learning Objectives'''

|| In this tutorial, we will learn about,

Change in concentration of the solution on:
*addition of a solute
*addition of a solvent
*evaporation

Conductivity of a solution

Identify whether the given compound is ionic or covalent.
|-
|| '''Slide Number 3'''

'''System Requirement'''
|| Here I am using

'''Windows 11 (64 bit).'''

'''Java version 1.8'''

|-
||'''Slide Number 4'''

'''Pre-requisites'''
'''[https://spoken-tutorial.org/ https://spoken-tutorial.org]'''

||To follow this tutorial, learner should be familiar with topics in high school science.

Please use the link below to access the tutorials on PhET Simulations.

|-
||'''Slide Number 5'''

'''Link for PhET simulation'''

point to

'''https://phet.colorado.edu/en/simulations/sugar-and-salt-solutions'''

||Please use the given link to download the PhET simulation.

|-
||'''Point to the file in the Downloads folder'''.
||I have downloaded '''Sugar and Salt Solutions''' simulation, to my '''Downloads''' folder.
|-
||'''Double click the file to open'''
||To open the simulation double click on the file.
|-
||'''Cursor on the interface.'''
||This is the interface of '''Sugar and Salt Solutions simulation'''
|-
|| Cursor on simulation interface.

Move the cursor on the tabs, '''Macro, Micro and Water'''.

|| The simulation interface has 3 tabs.

'''Macro, Micro '''and''' Water'''.
|-
|| Cursor on Macro interface.

|| '''Macro '''tab opens first by default.

The main panel shows a container with inlet and outlet water faucets.
|-
|| Show the location of inlet and outlet Faucets.
|| Inlet water faucet is placed at the top-left of the container.

Outlet water faucet is placed at the bottom-right of the container.
|-
|| Cursor on the container.
|| The container is graduated and filled with water.

The markings show 0 Litre, 1 Litre and 2 Litres.
|-
|| Show salt shaker.
|| A salt shaker is placed at the top of the container.

Shake the salt dispenser to add salt to the container.
|-
|| Cursor on the right panel.
|| On the right, we see '''Solute''', '''Concentration '''and''' Conductivity '''panels.
|-
|| Cursor on the right panel.

Point to the options.
|| From the '''Solute''' panel, the solute type can be selected.

The '''Solute''' panel shows '''Salt''' and '''Sugar''' radio buttons.

From here we can select the solute type.

Let us keep the default solute as salt.

|-
|| Cursor on the right panel.

Click on the show values checkbox
|| The '''Concentration''' panel shows the concentration as a bar graph.

Let us check the '''Show values''' checkbox to see the concentration values.
|-
|| Cursor to bottom panel

Drag the Evaporation slider from none to lots.
|| At the bottom we see '''Evaporation''' panel with a slider.

To evaporate water, drag the slider from '''none''' to '''lots'''.

Observe the change in the concentration in the '''Concentration''' panel.

As water evaporates the concentration of the salt increases.

|-
|| Cursor to the bottom of container
|| There is a '''Remove salt '''button at the bottom of the container.

On clicking this button salt is removed from the solution.
|-
|| Click the '''Reset All '''button.
|| '''Reset All '''button resets the simulation to default parameters.
|-
|| Cursor on the water container.

Click on the show value check box.
|| Let us observe the concentration of salt in water.

Let the water level in the container be at 1 litre mark.

Let us check the '''Show values''' box.
|-
|| Shake the salt dispenser.
|| Shake the salt shaker to add salt to the container.

|-
|| '''Slide Number 6'''

'''Definition of concentration'''

||

Concentration is a measure of the amount of solute dissolved in a given solution.

Molarity is one way of expressing concentration.

Molarity = Number of moles of the solute/Volume of the solution in litres(L)

Molarity (M) = n/Vyes after recording the concentration as a slide with table The show values values check box shows various values of molarity.

Using the molarity we can calculate the amount of salt added.

We can show a table here with different molarities and the respective weights.

|-
|| Cursor on concentration panel

Shake the dispenser to add salt
|| On adding salt, concentration increases as seen in the concentration panel.

I will record the change in concentration.
|-
|| '''Slide Number 7'''

'''Calculations'''
|| Solute in the shaker is 100 g

Molecular weight of sodium chloride(NaCl) is 58.44 g/mol

Molarity = Weight /(Molecular wt x V)

Molarity = 100 / (58.44 x 1)

Molarity <nowiki>= 1.72 M(molar)</nowiki>

|-
|| Cursor on concentration panel
|| Let us add more salt and record the change in concentration.

Let's tabulate the values to calculate the amount of solute.
|-
|| '''Slide Number 8'''

'''Table 1'''
|| Here I have calculated the amount of solute for different concentrations.

|-
||Drag the slider on the inlet Faucet.
||Let's add some water to the container till the 1.5 litres mark.

Observe the concentration in the panel.
|-
||Cursor on the simulation.
||A decrease in concentration is observed.

As per the formula concentration is inversely related to the volume of solution.

Hence on increasing the volume, concentration decreases.
|-
|| Cursor on Evaporation panel.

Slide the evaporation slider to the right.

Cursor to the concentration panel.
|| Now let us see the effect of '''evaporation''' on concentration.

I will drag the evaporation slider from '''none ''' to ''' lots '''to decrease the volume.

We can see an increase in concentration as the volume decreases.
|-
|| Cursor to the green electrode

Cursor to red electrode

Cursor to bulb and battery
|| Let us now check the '''Conductivity''' panel.

It has a circuit with a green negatively charged anode.

The red positively charged electrode acts as a cathode.

A bulb is connected to a battery to observe the luminescence conductivity.
|-
|| Cursor on the right panel.

Drag the circuit inside the solution

Cursor towards the blub
|| Now let us observe the conductivity of the solution.

Let us drag the circuit inside the solution.

The bulb glows now.
|-
|| Shake the salt dispenser.

Cursor to the bulb

|| Let's add more salt to the container.

The bulb glows brighter as the concentration of salt in the solution increases.

|-
|| Point to the bulb.
|| Dissociated salts conduct electricity through ions.

Hence intensity of brightness increases.
|-
|| Click on Reset all button

Click on the show values checkbox
||Click on the '''Reset All ''' button.

Let us select the '''Show values''' checkbox in the Concentration panel.
|-
|| Cursor on the water container.

|| Let us observe the concentration of sugar in water.

Click on the '''Sugar '''radio button to select sugar as solute.
|-
|| Shake the sugar dispenser.
|| Let's add sugar to the container.

|-
|| Cursor on concentration panel

Shake the dispenser to add salt
|| On adding sugar concentration increases as seen in the Concentration panel.

Let's add more sugar to the container and record the concentration.

Let's tabulate the results.
|-
|| '''Slide Number 9'''

'''Table 2'''
|| Molecular weight of sugar is 342.3 g/mol

Here I have calculated the amount of sugar for different concentrations.
|-
|| Cursor on right panel.

Drag the circuit inside the solution

Cursor towards the blub
|| Let us observe the conductivity of sugar solution.

Drag and place the circuit inside the solution.

This time the bulb does not glow.
|-
|| Point to the solution and bulb.

|| This is because sugar does not dissociate into ions.

Hence cannot conduct electricity.

|-
|| Click on the micro tab to open.
|| To observe this phenomenon in detail click the '''Micro '''tab to open it.
|-
|| Cursor on the interface.
|| In the '''Micro''' tab, molecular movement of ions can be observed in the solution.
|-
|| Cursor on right panel.

|| On the right, you will see '''Solute '''and '''Concentration '''panels.

The '''Solute '''panel shows different solutes.

Let us look at the '''Concentration''' panel.

Here sodium ion is shown as a purple sphere and chloride ion as green sphere.

'''Sucrose''' is represented as a molecule with white, grey and red spheres.
|-
|| Cursor on the water container.

Cursor on pause and slow button

|| I will keep Sodium chloride as the default solute.

On the bottom left '''pause''' and '''slow-motion''' buttons can be seen.

Slow-motion button can be used to observe the dissociation in slow motion.
|-
|| Shake salt shaker in a container,

Click on the pause button.

Click the slow-motion button multiple times.

Cursor in right panel
|| Let us add sodium chloride to the container using the salt shaker.

Click the '''pause''' button as soon as the molecules touch the surface of water.

Now click the '''slow-motion''' button multiple times to observe slow dissociation.

I will continue to click the button until all the atoms ionize.

On adding the salt to water it dissociates into ions of opposite charges.

Observe the increase in concentration of the ions in the right panel.
|-
|| Cursor on the right panel.

Click on the Sucrose option in the solute panel.

Add Sucrose
to the container.

Cursor towards the container.
|| Let's click the '''Reset All''' button to reset the simulation to default parameters.

Now I will change the solute to '''Sucrose'''.

Let's add '''Sucrose''' to the container.

As observed, '''Sucrose ''' does not dissociate into ions.
|-
|| Point to the molecules in the container.
|| Sucrose will not dissociate, as it is a molecular solid with covalent bonding.

So it will not show conductivity as shown by salts.

This explains the conductivity of salts but not sugar.
|-
|| Click the arrow button to show the solutes.
|| Now slide the '''solute''' panel to explore more solutes.

You can practise with the other solutes present in the panel.

|-
|| Cursor on Periodic table button.

Click on the button.

Close the periodic table box.
|| The''' Periodic table button''' is present in the right panel.

This gives information about the elements present in the selected molecule.

They can be individually identified as metals or non-metals.

Close the periodic table box.
|-
|| Click on the Water tab.

Cursor on magnified view.
|| Now click on the '''Water''' tab.

It shows a magnified version of molecular interactions between water molecules.

|-
|| Point to sugar and salt in molecular form.
|| Interface shows salt and sugar as solutes in molecular form.
|-
|| Cursor on the right panel.

Cursor on options and buttons.

Point to sugar highlight option.

Point to the sugar molecules in the Sugar bucket.

Uncheck the '''Sugar highlight '''option.

Point to the sugar molecules in the Sugar bucket.

Click the '''Water partial charges''' option.

Cursor on water partial charges in the container.
|| On the bottom right panel, you will see the '''Show '''panel.

It has two options, Water partial charges and Sugar highlight .

Sugar highlight option is selected by default.

Here the sugar molecules are highlighted in yellow colour.

Lets uncheck the '''Sugar highlight '''option.

Observe that sugar molecules appear in their default colours.

Click the '''Water partial charges''' option.

Partial charges are shown on all water molecules.

|-
|| Cursor on the button.

Click on the '''Sugar in 3D '''button.

Point to the model in the window.

Click on the Ball and stick model.
|| In the right panel, we can also see a '''Sugar in 3D '''button.

Now I will click the '''Sugar in 3D''' button.

A window opens with a 3D model of sugar in '''space fill''' format.

Now Let's select the Ball and stick option.

The sticks in the model represent covalent bonds between adjacent atoms.
|-
|| Click on the X button to close.
|| Let us close the window.
|-
|| Add salt and pause the simulation.

Cursor on the magnified view.

Cursor on negatively charged charges.

Cursor on positively charged charges.

|| Now let's add salt to water and immediately pause the simulation.

Observe the orientation of water's partial charges with sodium and chloride ions.

Negative partial charges coloured red are aligned around sodium ions.

Positive charges coloured white are aligned around chloride ions.

This demonstrates the dissociation at molecular level in the water.
|-
||Click on the '''Reset All'''.

Click on the water partial charges option.
||Click on the '''Reset All '''button on the right panel.

Select the water partial charges option in the '''Show''' panel.
|-
|| Add sugar to water and pause the simulation.

Cursor on magnified view.
|| Now add sugar to water and immediately pause the simulation.

This time the molecules are not aligned nor do they dissociate.

This is because sugar is a complex molecule with covalent bonds.

This resists its dissociation in water so no ions are formed.
|-
|| '''Slide Number 7'''

'''Summary'''
|| With this we come to the end of this tutorial.

Let's summarise.

In this tutorial we have learnt about,

Change in concentration of the solution on:
*addition of a solute
*addition of a solvent
*evaporation

Conductivity of a solution.

Identify whether the given compound is ionic or covalent.
|-
|| '''Slide Number 8'''

'''Assignment'''
||

As an assignment,

Explore more solutes and observe their dissociation in water.

Interpret the possible dissociated ions and predict their conductivity.
|-
|| '''Slide''': 9

'''About Spoken Tutorial Project '''
||The video at the following link summarizes the Spoken Tutorial project.
*Please download and watch it.

|-
|| '''Slide''': 10

'''Spoken tutorial workshops '''
||We conduct workshops using spoken tutorials and give certificates.
*For more details, please contact us.

|-
|| '''Slide''': 11

'''Answers for THIS Spoken Tutorial '''

Do you have questions in THIS Spoken Tutorial?

Please visit this site

Choose the minute and second where you have the question.

Explain your question briefly

The spoken tutorial project will ensure answer.

You will have to register on this website to ask questions.
|| * <div style="margin-left:1.245cm;margin-right:0cm;">Please post your timed queries in this forum.

|-
|| '''Slide''': 17

'''Forum '''
||The Spoken Tutorial forum is for specific questions on this tutorial.
*Please do not post unrelated and general questions on them.
*This will help reduce the clutter.
*With less clutter, we can use these discussions as instructional material.

|-
|| '''Slide''': 12

'''Acknowledgement '''
|| Spoken Tutorial project is funded by the Ministry of Education (MoE), Govt. of India
|-
||
||This is Vidhi Thakur, a FOSSEE
*summer fellow 2022, IIT Bombay
*signing off

Thank you for joining.

|-
|}

PhET-Simulations-for-Chemistry/C3/Sugar-and-Salt-solutions/English

2022-11-17T06:26:01Z

Vidhithakur:

'''Sugar and Salt Solutions'''

'''Author: Vidhi Thakur'''

'''Keywords: '''PhET simulation''', '''Sugar, Salts, solute, molarity, concentration, evaporation, Conductivity, water partial charges, space fill format and Ball and stick format, spoken tutorial, video tutorial.

{|border=1
|-
||'''Visual Cue'''
||'''Narration'''
|-
|| '''Slide Number 1'''

'''Title Slide'''
|| Welcome to this tutorial on '''Sugar and Salt solutions.'''
|-
|| '''Slide Number 2'''

'''Learning Objectives'''

|| In this tutorial, we will learn about,

Change in concentration of the solution on:
*addition of a solute
*addition of a solvent
*evaporation

Conductivity of a solution

Identify whether the given compound is ionic or covalent.
|-
|| '''Slide Number 3'''

'''System Requirement'''
|| Here I am using

'''Windows 11 (64 bit).'''

'''Java version 1.8'''

|-
||'''Slide Number 4'''

'''Pre-requisites'''
'''[https://spoken-tutorial.org/ https://spoken-tutorial.org]'''

||To follow this tutorial, learner should be familiar with topics in high school science.

Please use the link below to access the tutorials on PhET Simulations.

|-
||'''Slide Number 5'''

'''Link for PhET simulation'''

point to

'''https://phet.colorado.edu/en/simulations/sugar-and-salt-solutions'''

||Please use the given link to download the PhET simulation.

|-
||'''Point to the file in the Downloads folder'''.
||I have downloaded '''Sugar and Salt Solutions''' simulation, to my '''Downloads''' folder.
|-
||'''Double click the file to open'''
||To open the simulation double click on the file.
|-
||'''Cursor on the interface.'''
||This is the interface of '''Sugar and Salt Solutions simulation'''
|-
|| Cursor on simulation interface.

Move the cursor on the tabs, '''Macro, Micro and Water'''.

|| The simulation interface has 3 tabs.

'''Macro, Micro '''and''' Water'''.
|-
|| Cursor on Macro interface.

|| '''Macro '''tab opens first by default.

The main panel shows a container with inlet and outlet water faucets.
|-
|| Show the location of inlet and outlet Faucets.
|| Inlet water faucet is placed at the top-left of the container.

Outlet water faucet is placed at the bottom-right of the container.
|-
|| Cursor on the container.
|| The container is graduated and filled with water.

The markings show 0 Litre, 1 Litre and 2 Litres.
|-
|| Show salt shaker.
|| A salt shaker is placed at the top of the container.

Shake the salt dispenser to add salt to the container.
|-
|| Cursor on the right panel.
|| On the right, we see '''Solute''', '''Concentration '''and''' Conductivity '''panels.
|-
|| Cursor on the right panel.

Point to the options.
|| From the '''Solute''' panel, the solute type can be selected.

The '''Solute''' panel shows '''Salt''' and '''Sugar''' radio buttons.

From here we can select the solute type.

Let us keep the default solute as salt.

|-
|| Cursor on the right panel.

Click on the show values checkbox
|| The '''Concentration''' panel shows the concentration as a bar graph.

Let us check the '''Show values''' checkbox to see the concentration values.
|-
|| Cursor to bottom panel

Drag the Evaporation slider from none to lots.
|| At the bottom we see '''Evaporation''' panel with a slider.

To evaporate water, drag the slider from '''none''' to '''lots'''.

Observe the change in the concentration in the '''Concentration''' panel.

As water evaporates the concentration of the salt increases.

|-
|| Cursor to the bottom of container
|| There is a '''Remove salt '''button at the bottom of the container.

On clicking this button salt is removed from the solution.
|-
|| Click the '''Reset All '''button.
|| '''Reset All '''button resets the simulation to default parameters.
|-
|| Cursor on the water container.

Click on the show value check box.
|| Let us observe the concentration of salt in water.

Let the water level in the container be at 1 litre mark.

Let us check the '''Show values''' box.
|-
|| Shake the salt dispenser.
|| Shake the salt shaker to add salt to the container.

|-
|| '''Slide Number 6'''

'''Definition of concentration'''

||

Concentration is a measure of the amount of solute dissolved in a given solution.

Molarity is one way of expressing concentration.

Molarity = Number of moles of the solute/Volume of the solution in litres(L)

Molarity (M) = n/Vyes after recording the concentration as a slide with table The show values values check box shows various values of molarity.

Using the molarity we can calculate the amount of salt added.

We can show a table here with different molarities and the respective weights.

|-
|| Cursor on concentration panel

Shake the dispenser to add salt
|| On adding salt, concentration increases as seen in the concentration panel.

I will record the change in concentration.
|-
|| '''Slide Number 7'''

'''Calculations'''
|| Solute in the shaker is 100 g

Molecular weight of sodium chloride(NaCl) is 58.44 g/mol

Molarity = Weight /(Molecular wt x V)

Molarity = 100 / (58.44 x 1)

Molarity <nowiki>= 1.72 M(molar)</nowiki>

|-
|| Cursor on concentration panel
|| Let us add more salt and record the change in concentration.

Let's tabulate the values to calculate the amount of solute.
|-
|| '''Slide Number 8'''

'''Table 1'''
|| Here I have calculated the amount of solute for different concentrations.
|-
||

|-
||Drag the slider on the inlet Faucet.
||Let's add some water to the container till the 1.5 litres mark.

Observe the concentration in the panel.
|-
||Cursor on the simulation.
||A decrease in concentration is observed.

As per the formula concentration is inversely related to the volume of solution.

Hence on increasing the volume, concentration decreases.
|-
|| Cursor on Evaporation panel.

Slide the evaporation slider to the right.

Cursor to the concentration panel.
|| Now let us see the effect of '''evaporation''' on concentration.

I will drag the evaporation slider from '''none ''' to ''' lots '''to decrease the volume.

We can see an increase in concentration as the volume decreases.
|-
|| Cursor to the green electrode

Cursor to red electrode

Cursor to bulb and battery
|| Let us now check the '''Conductivity''' panel.

It has a circuit with a green negatively charged anode.

The red positively charged electrode acts as a cathode.

A bulb is connected to a battery to observe the luminescence conductivity.
|-
|| Cursor on the right panel.

Drag the circuit inside the solution

Cursor towards the blub
|| Now let us observe the conductivity of the solution.

Let us drag the circuit inside the solution.

The bulb glows now.
|-
|| Shake the salt dispenser.

Cursor to the bulb

|| Let's add more salt to the container.

The bulb glows brighter as the concentration of salt in the solution increases.

|-
|| Point to the bulb.
|| Dissociated salts conduct electricity through ions.

Hence intensity of brightness increases.
|-
|| Click on Reset all button

Click on the show values checkbox
||Click on the '''Reset All ''' button.

Let us select the '''Show values''' checkbox in the Concentration panel.
|-
|| Cursor on the water container.

|| Let us observe the concentration of sugar in water.

Click on the '''Sugar '''radio button to select sugar as solute.
|-
|| Shake the sugar dispenser.
|| Let's add sugar to the container.

|-
|| Cursor on concentration panel

Shake the dispenser to add salt
|| On adding sugar concentration increases as seen in the Concentration panel.

Let's add more sugar to the container and record the concentration.

Let's tabulate the results.
|-
|| '''Slide Number 9'''

'''Table 2'''
|| Molecular weight of sugar is 342.3 g/mol

Here I have calculated the amount of sugar for different concentrations.
|-
|| Cursor on right panel.

Drag the circuit inside the solution

Cursor towards the blub
|| Let us observe the conductivity of sugar solution.

Drag and place the circuit inside the solution.

This time the bulb does not glow.
|-
|| Point to the solution and bulb.

|| This is because sugar does not dissociate into ions.

Hence cannot conduct electricity.

|-
|| Click on the micro tab to open.
|| To observe this phenomenon in detail click the '''Micro '''tab to open it.
|-
|| Cursor on the interface.
|| In the '''Micro''' tab, molecular movement of ions can be observed in the solution.
|-
|| Cursor on right panel.

|| On the right, you will see '''Solute '''and '''Concentration '''panels.

The '''Solute '''panel shows different solutes.

Let us look at the '''Concentration''' panel.

Here sodium ion is shown as a purple sphere and chloride ion as green sphere.

'''Sucrose''' is represented as a molecule with white, grey and red spheres.
|-
|| Cursor on the water container.

Cursor on pause and slow button

|| I will keep Sodium chloride as the default solute.

On the bottom left '''pause''' and '''slow-motion''' buttons can be seen.

Slow-motion button can be used to observe the dissociation in slow motion.
|-
|| Shake salt shaker in a container,

Click on the pause button.

Click the slow-motion button multiple times.

Cursor in right panel
|| Let us add sodium chloride to the container using the salt shaker.

Click the '''pause''' button as soon as the molecules touch the surface of water.

Now click the '''slow-motion''' button multiple times to observe slow dissociation.

I will continue to click the button until all the atoms ionize.

On adding the salt to water it dissociates into ions of opposite charges.

Observe the increase in concentration of the ions in the right panel.
|-
|| Cursor on the right panel.

Click on the Sucrose option in the solute panel.

Add Sucrose
to the container.

Cursor towards the container.
|| Let's click the '''Reset All''' button to reset the simulation to default parameters.

Now I will change the solute to '''Sucrose'''.

Let's add '''Sucrose '''to the container.

As observed, '''Sucrose ''' does not dissociate into ions.
|-
|| Point to the molecules in the container.
|| Sucrose will not dissociate, as it is a molecular solid with covalent bonding.

So it will not show conductivity as shown by salts.

This explains the conductivity of salts but not sugar.
|-
|| Click the arrow button to show the solutes.
|| Now slide the '''solute''' panel to explore more solutes.

You can practise with the other solutes present in the panel.

|-
|| Cursor on Periodic table button.

Click on the button.

Close the periodic table box.
|| The''' Periodic table button''' is present in the right panel.

This gives information about the elements present in the selected molecule.

They can be individually identified as metals or non-metals.

Close the periodic table box.
|-
|| Click on the Water tab.

Cursor on magnified view.
|| Now click on the '''Water''' tab.

It shows a magnified version of molecular interactions between water molecules.

|-
|| Point to sugar and salt in molecular form.
|| Interface shows salt and sugar as solutes in molecular form.
|-
|| Cursor on the right panel.

Cursor on options and buttons.

Point to sugar highlight option.

Point to the sugar molecules in the Sugar bucket.

Uncheck the '''Sugar highlight '''option.

Point to the sugar molecules in the Sugar bucket.

Click the '''Water partial charges''' option.

Cursor on water partial charges in the container.
|| On the bottom right panel, you will see the '''Show '''panel.

It has two options, Water partial charges and Sugar highlight .

Sugar highlight option is selected by default.

Here the sugar molecules are highlighted in yellow colour.

Lets uncheck the '''Sugar highlight '''option.

Observe that sugar molecules appear in their default colours.

Click the '''Water partial charges''' option.

Partial charges are shown on all water molecules.

|-
|| Cursor on the button.

Click on the '''Sugar in 3D '''button.

Point to the model in the window.

Click on the Ball and stick model.
|| In the right panel, we can also see a '''Sugar in 3D '''button.

Now I will click the '''Sugar in 3D''' button.

A window opens with a 3D model of sugar in '''space fill''' format.

Now Let's select the Ball and stick option.

The sticks in the model represent covalent bonds between adjacent atoms.
|-
|| Click on the X button to close.
|| Let us close the window.
|-
|| Add salt and pause the simulation.

Cursor on the magnified view.

Cursor on negatively charged charges.

Cursor on positively charged charges.

|| Now let's add salt to water and immediately pause the simulation.

Observe the orientation of water's partial charges with sodium and chloride ions.

Negative partial charges coloured red are aligned around sodium ions.

Positive charges coloured white are aligned around chloride ions.

This demonstrates the dissociation at molecular level in the water.
|-
||Click on the '''Reset All'''.

Click on the water partial charges option.
||Click on the '''Reset All '''button on the right panel.

Select the water partial charges option in the '''Show''' panel.
|-
|| Add sugar to water and pause the simulation.

Cursor on magnified view.
|| Now add sugar to water and immediately pause the simulation.

This time the molecules are not aligned nor do they dissociate.

This is because sugar is a complex molecule with covalent bonds.

This resists its dissociation in water so no ions are formed.
|-
|| '''Slide Number 7'''

'''Summary'''
|| With this we come to the end of this tutorial.

Let's summarise.

In this tutorial we have learnt about,

Change in concentration of the solution on:
*addition of a solute
*addition of a solvent
*evaporation

Conductivity of a solution.

Identify whether the given compound is ionic or covalent.
|-
|| '''Slide Number 8'''

'''Assignment'''
||

As an assignment,

Explore more solutes and observe their dissociation in water.

Interpret the possible dissociated ions and predict their conductivity.
|-
|| '''Slide''': 9

'''About Spoken Tutorial Project '''
||The video at the following link summarizes the Spoken Tutorial project.
*Please download and watch it.

|-
|| '''Slide''': 10

'''Spoken tutorial workshops '''
||We conduct workshops using spoken tutorials and give certificates.
*For more details, please contact us.

|-
|| '''Slide''': 11

'''Answers for THIS Spoken Tutorial '''

Do you have questions in THIS Spoken Tutorial?

Please visit this site

Choose the minute and second where you have the question.

Explain your question briefly

The spoken tutorial project will ensure answer.

You will have to register on this website to ask questions.
|| * <div style="margin-left:1.245cm;margin-right:0cm;">Please post your timed queries in this forum.

|-
|| '''Slide''': 17

'''Forum '''
||The Spoken Tutorial forum is for specific questions on this tutorial.
*Please do not post unrelated and general questions on them.
*This will help reduce the clutter.
*With less clutter, we can use these discussions as instructional material.

|-
|| '''Slide''': 12

'''Acknowledgement '''
|| Spoken Tutorial project is funded by the Ministry of Education (MoE), Govt. of India
|-
||
||This is Vidhi Thakur, a FOSSEE
*summer fellow 2022, IIT Bombay
*signing off

Thank you for joining.

|-
|}

PhET-Simulations-for-Chemistry/C3/Sugar-and-Salt-solutions/English

2022-11-17T05:52:08Z

Vidhithakur: Created page with "'''Sugar and Salt Solutions''' '''Author: Vidhi Thakur''' '''Keywords: '''PhET simulation''', '''Sugar, Salts, solute, molarity, concentration, evaporation, Conductivity,..."

'''Sugar and Salt Solutions'''

'''Author: Vidhi Thakur'''

'''Keywords: '''PhET simulation''', '''Sugar, Salts, solute, molarity, concentration, evaporation, Conductivity, water partial charges, space fill format and Ball and stick format, spoken tutorial, video tutorial.

{|border=1
|-
||'''Visual Cue'''
||'''Narration'''
|-
|| '''Slide Number 1'''

'''Title Slide'''
|| Welcome to this tutorial on '''Sugar and Salt solutions.'''
|-
|| '''Slide Number 2'''

'''Learning Objectives'''

|| In this tutorial, we will learn about,

*Change in concentration of the solution on:
*addition of a solute
*addition of a solvent
*evaporation

Conductivity of a solution

Identify whether the given compound is ionic or covalent.
|-
|| '''Slide Number 3'''

'''System Requirement'''
|| Here I am using

'''Windows 11 (64 bit).'''

'''Java version 1.8'''

|-
||'''Slide Number 4'''

'''Pre-requisites'''
||To follow this tutorial, learner should be familiar with topics in high school science.

Please use the link below to access the tutorials on PhET Simulations.

|-
||'''Slide Number 5'''

'''Link for PhET simulation'''

point to

'''https://phet.colorado.edu/en/simulations/sugar-and-salt-solutions'''
||'''Please use the given link to download the PhET simulation.'''

'''https://phet.colorado.edu/en/simulations/sugar-and-salt-solutions'''

|-
||'''Point to the file in the Downloads folder'''.
||I have downloaded'''Sugar and Salt Solutions'''simulation, to my'''Downloads'''folder.
|-
||'''Double click the file to open'''
||To open the simulation double click on the file.
|-
||'''Cursor on the interface.'''
||This is the interface of'''Sugar and Salt Solutions simulation'''
|-
|| Cursor on simulation interface.

Move the cursor on the tabs, '''Macro, Micro and Water'''.

|| The simulation interface has 3 tabs.

'''Macro, Micro '''and''' Water'''.
|-
|| Cursor on Macro interface.

|| '''Macro '''tab opens first by default.

The main panel shows a container with inlet and outlet water faucets.
|-
|| Show the location of inlet and outlet Faucets.
|| Inlet water faucet is placed at the top-left of the container.

Outlet water faucet is placed at the bottom-right of the container.
|-
|| Cursor on the container.
|| The container is graduated and filled with water.

The markings show 0 Litre, 1 Litre and 2 Litres.
|-
|| Show salt shaker.
|| A salt shaker is placed at the top of the container.

Shake the salt dispenser to add salt to the container.
|-
|| Cursor on the right panel.
|| On the right, we see '''Solute''', '''Concentration '''and''' Conductivity '''panels.
|-
|| Cursor on the right panel.

Point to the options.
|| From the '''Solute''' panel, the solute type can be selected.

The '''Solute''' panel shows '''Salt''' and '''Sugar''' radio buttons.

From here we can select the solute type.

Let us keep the default solute as salt.

|-
|| Cursor on the right panel.

Click on the show values checkbox
|| The '''Concentration''' panel shows the concentration as a bar graph.

Let us check the '''Show values''' checkbox to see the concentration values.
|-
|| Cursor to bottom panel

Drag the Evaporation slider from none to lots.
|| At the bottom we see '''Evaporation''' panel with a slider.

To evaporate water, drag the slider from '''none''' to '''lots'''.

Observe the change in the concentration in the '''Concentration''' panel.

As water evaporates the concentration of the salt increases.

|-
|| Cursor to the bottom of container
|| There is a '''Remove salt '''button at the bottom of the container.

On clicking this button salt is removed from the solution.
|-
|| Click the '''Reset All '''button.
|| '''Reset All '''button resets the simulation to default parameters.
|-
|| Cursor on the water container.

Click on the show value check box.
|| Let us observe the concentration of salt in water.

Let the water level in the container be at 1 litre mark.

Let us check the '''Show values''' box.
|-
|| Shake the salt dispenser.
|| Shake the salt shaker to add salt to the container.

|-
|| '''Slide Number 6'''

'''Definition of concentration'''

||

Concentration is a measure of the amount of solute dissolved in a given solution.

Molarity is one way of expressing concentration.

Molarity = Number of moles of the solute/Volume of the solution in litres(L)

Molarity (M) = n/Vyes after recording the concentration as a slide with tableThe show values values check box shows various values of molarity.

Using the molarity we can calculate the amount of salt added.

We can show a table here with different molarities and the respective weights.

|-
||
||
|-
|| '''Slide Number 6'''

|-
|| Cursor on concentration panel

Shake the dispenser to add salt
|| On adding salt, concentration increases as seen in the concentration panel.

I will record the change in concentration.
|-
|| '''Slide Number 7'''

'''Calculations'''
|| Solute in the shaker is 100 g

Molecular weight of sodium chloride(NaCl) is 58.44 g/mol

Molarity = Weight /(Molecular wt x V)

Molarity = 100 / (58.44 x 1)

Molarity <nowiki>= 1.72 M(molar)</nowiki>

|-
|| Cursor on concentration panel
|| Let us add more salt and record the change in concentration.

Letâ€™s tabulate the values to calculate the amount of solute.
|-
|| '''Slide Number 8'''

'''Table 1'''
|| Here I have calculated the amount of solute for different concentrations.
|-
||
||
|-
||Drag the slider on the inlet Faucet.
||Letâ€™s add some water to the container till the 1.5 litres mark.okayhere you can specify how much water is added as the container is graduated.

Observe the concentration in the panel.
|-
||Cursor on the simulation.
||A decrease in concentration is observed.

As per the formula concentration is inversely related to the volume of solution.

Hence on increasing the volume, concentration decreases.
|-
|| Cursor on Evaporation panel.

Slide the evaporation slider to the right.

Cursor to the concentration panel.
|| Now let us see the effect of '''evaporation''' on concentration.

I will drag the evaporation slider from '''none '''to''' lots '''to decrease the volume.

We can see an increase in concentration as the volume decreases.
|-
|| Cursor to the green electrode

Cursor to red electrode

Cursor to bulb and battery
|| Let us now check the '''Conductivity''' panel.

It has a circuit with a green negatively charged anode.

The red positively charged electrode acts as a cathode.

A bulb is connected to a battery to observe the luminescence conductivity.
|-
|| Cursor on the right panel.

Drag the circuit inside the solution

Cursor towards the blub
|| Now let us observe the conductivity of the solution.

Let us drag the circuit inside the solution.

The bulb glows now.
|-
|| Shake the salt dispenser.

Cursor to the bulb

|| Letâ€™s add more salt to the container.

The bulb glows brighter as the concentration of salt in the solution increases.

|-
|| Point to the bulb.
|| Dissociated salts conduct electricity through ions.

Hence intensity of brightness increases.
|-
|| Click on Reset all button

Click on the show values checkbox
||Click on the'''Reset All '''button.

Let us select the '''Show values''' checkbox in the Concentration panel.
|-
|| Cursor on the water container.

|| Let us observe the concentration of sugar in water.

Click on the'''Sugar '''radio button to select sugar as solute.
|-
|| Shake the sugar dispenser.
|| Letâ€™s add sugar to the container.

|-
|| Cursor on concentration panel

Shake the dispenser to add salt
|| On adding sugar concentration increases as seen in the Concentration panel.

Letâ€™s add more sugar to the container and record the concentration.

Letâ€™s tabulate the results.
|-
|| '''Slide Number 9'''

'''Table 2'''
|| Molecular weight of sugar is 342.3 g/mol

Here I have calculated the amount of sugar for different concentrations.
|-
|| Cursor on right panel.

Drag the circuit inside the solution

Cursor towards the blub
|| Let us observe the conductivity of sugar solution.

Drag and place the circuit inside the solution.

This time the bulb does not glow.
|-
|| Point to the solution and bulb.

|| This is because sugar does not dissociate into ions.

Hence cannot conduct electricity.

|-
|| Click on the micro tab to open.
|| To observe this phenomenon in detail click the '''Micro '''tab to open it.
|-
|| Cursor on the interface.
|| In the '''Micro''' tab, molecular movement of ions can be observed in the solution.
|-
|| Cursor on right panel.

|| On the right, you will see '''Solute '''and '''Concentration '''panels.

The '''Solute '''panel shows different solutes.

Let us look at the '''Concentration''' panel.

Here sodium ion is shown as a purple sphere and chloride ion as green sphere.

'''Sucrose''' is represented as a molecule with white, grey and red spheres.
|-
|| Cursor on the water container.

Cursor on pause and slow button

|| I will keep Sodium chloride as the default solute.

On the bottom left '''pause''' and '''slow-motion''' buttons can be seen.

Slow-motion button can be used to observe the dissociation in slow motion.
|-
|| Shake salt shaker in a container,

Click on the pause button.

Click the slow-motion button multiple times.

Cursor in right panel
|| Let us add sodium chloride to the container using the salt shaker.

Click the '''pause''' button as soon as the molecules touch the surface of water.

Now click the '''slow-motion''' button multiple times to observe slow dissociation.

I will continue to click the button until all the atoms ionize.

On adding the salt to water it dissociates into ions of opposite charges.

Observe the increase in concentration of the ions in the right panel.
|-
|| Cursor on the right panel.

Click on the Sucrose option in the solute panel.

Add Sucrose
to the container.

Cursor towards the container.
|| Letâ€™s click the '''Reset All''' button to reset the simulation to default parameters.

Now I will change the solute to '''Sucrose'''.

Letâ€™s add '''Sucrose '''to the container.

As observed, '''Sucrose '''does not dissociate into ions.
|-
|| Point to the molecules in the container.
|| Sucrose will not dissociate, as it is a molecular solid with covalent bonding.

So it will not show conductivity as shown by salts.

This explains the conductivity of salts but not sugar.
|-
|| Click the arrow button to show the solutes.
|| Now slide the '''solute''' panel to explore more solutes.

You can practise with the other solutes present in the panel.

|-
|| Cursor on Periodic table button.

Click on the button.

Close the periodic table box.
|| The''' Periodic table button''' is present in the right panel.

This gives information about the elements present in the selected molecule.

They can be individually identified as metals or non-metals.

Close the periodic table box.
|-
|| Click on the Water tab.

Cursor on magnified view.
|| Now click on the '''Water''' tab.

It shows a magnified version of molecular interactions between water molecules.

|-
|| Point to sugar and salt in molecular form.
|| Interface shows salt and sugar as solutes in molecular form.
|-
|| Cursor on the right panel.

Cursor on options and buttons.

Point to sugar highlight option.

Point to the sugar molecules in the Sugar bucket.

Uncheck the '''Sugar highlight '''option.

Point to the sugar molecules in the Sugar bucket.

Click the '''Water partial charges''' option.

Cursor on water partial charges in the container.
|| On the bottom right panel, you will see the '''Show '''panel.

It has two options, Water partial charges and Sugar highlight .

Sugar highlight option is selected by default.

Here the sugar molecules are highlighted in yellow colour.

Lets uncheck the '''Sugar highlight '''option.

Observe that sugar molecules appear in their default colours.

Click the '''Water partial charges''' option.

Partial charges are shown on all water molecules.

|-
|| Cursor on the button.

Click on the '''Sugar in 3D '''button.

Point to the model in the window.

Click on the Ball and stick model.
|| In the right panel, we can also see a '''Sugar in 3D '''button.

Now I will click the '''Sugar in 3D''' button.

A window opens with a 3D model of sugar in '''space fill''' format.

Now Letâ€™s select the Ball and stick option.

The sticks in the model represent covalent bonds between adjacent atoms.
|-
|| Click on the X button to close.
|| Let us close the window.
|-
|| Add salt and pause the simulation.

Cursor on the magnified view.

Cursor on negatively charged charges.

Cursor on positively charged charges.

|| Now letâ€™s add salt to water and immediately pause the simulation.

Observe the orientation of waterâ€™s partial charges with sodium and chloride ions.

Negative partial charges coloured red are aligned around sodium ions.

Positive charges coloured white are aligned around chloride ions.

This demonstrates the dissociation at molecular level in the water.
|-
||Click on the'''Reset All'''.

Click on the water partial charges option.
||Click on the'''Reset All '''button on the right panel.

Select the water partial charges option in the '''Show''' panel.
|-
|| Add sugar to water and pause the simulation.

Cursor on magnified view.
|| Now add sugar to water and immediately pause the simulation.

This time the molecules are not aligned nor do they dissociate.

This is because sugar is a complex molecule with covalent bonds.

This resists its dissociation in water so no ions are formed.
|-
|| '''Slide Number 7'''

'''Summary'''
|| With this we come to the end of this tutorial.

Let's summarise.

In this tutorial we have learnt about,

Change in concentration of the solution on:
*addition of a solute
*addition of a solvent
*evaporation

Conductivity of a solution.

Identify whether the given compound is ionic or covalent.
|-
|| '''Slide Number 8'''

'''Assignment'''
||

As an assignment,

Explore more solutes and observe their dissociation in water.

Interpret the possible dissociated ions and predict their conductivity.
|-
|| '''Slide''': 9

'''About Spoken Tutorial Project '''
||The video at the following link summarizes the Spoken Tutorial project.
*Please download and watch it.

|-
|| '''Slide''': 10

'''Spoken tutorial workshops '''
||We conduct workshops using spoken tutorials and give certificates.
*For more details, please contact us.

|-
|| '''Slide''': 11

'''Answers for THIS Spoken Tutorial '''

Do you have questions in THIS Spoken Tutorial?

Please visit this site

Choose the minute and second where you have the question.

Explain your question briefly

The spoken tutorial project will ensure answer.

You will have to register on this website to ask questions.
|| * <div style="margin-left:1.245cm;margin-right:0cm;">Please post your timed queries in this forum.

|-
|| '''Slide''': 17

'''Forum '''
||The Spoken Tutorial forum is for specific questions on this tutorial.
*Please do not post unrelated and general questions on them.
*This will help reduce the clutter.
*With less clutter, we can use these discussions as instructional material.

|-
|| '''Slide''': 12

'''Acknowledgement '''
|| Spoken Tutorial project is funded by the Ministry of Education (MoE), Govt. of India
|-
||
||This is Vidhi Thakur, a FOSSEE
*summer fellow 2022, IIT Bombay
*signing off

Thank you for joining.

|-
|}

PhET-Simulations-for-Chemistry/C3/Salts-and-Solubility/English

2022-11-05T06:00:34Z

Vidhithakur:

'''Salts and Solubility '''

'''Author: Snehalatha Kaliappan'''

'''Keywords: '''Salts, sparingly soluble salts, solubility, molar solubility, solubility product, molarity, Le Chaterlier’s principle, equilibrium expression, video tutorial

{|border=1
|-
||'''Visual Cue'''
||'''Narration'''
|-
|| '''Slide Number 1'''

'''Title Slide'''
|| Welcome to this tutorial on '''Salts and Solubility'''
|-
|| '''Slide Number 2'''

'''Learning Objectives'''
|| In this tutorial, we will learn about,

*Solubility of different salts.

*Create a neutral compound from anions and cations.

*Equilibrium expression for dissolution of salt in water.

*Calculate the molarity of solutions.

*Calculate Solubility Product of the salts.

|-
|| '''Slide Number 3'''

'''Learning Objectives'''
|| Application of Le Chaterlier’s principle to the dissolution of salts

*Design a salt with various combinations of charges and Solubility Products.

*Use Solubility Product values to predict solubility.

|-
|| '''Slide Number 3'''

'''System Requirement'''
|| Here I am using

'''Windows 11 (64 bit).'''

'''Java version 1.8'''
|-
|| '''Slide Number 4'''

'''Pre-requisites'''

'''[https://spoken-tutorial.org/ https://spoken-tutorial.org]'''

|| To follow this tutorial learner should be familiar with,

topics in high school science.

Please use the link below to access the tutorials on PhET Simulations.

|-
|| '''Slide Number 5'''

'''Link for PhET simulation'''

point to

'''https://phet.colorado.edu/en/simulations/soluble-salts'''

|| Please use the given link to download the PhET simulation.

|-
|| '''Point to the file in Downloads folder.'''
|| I have downloaded the '''Salts & Solubility '''simulation, to my Downloads folder.
|-
|| '''Double click the file to open'''
|| To open the simulation double click on the file.
|-
|| '''Cursor on the interface.'''
|| This is the interface of '''salt and solubility simulation'''.
|-
||

Cursor moves across the tabs.
||

It has 3 tabs.
|-
|| Cursor on Table Salt interface.

|| '''Table Salt '''tab opens first by default.

The main panel shows a container with inlet and outlet water taps.
|-
|| Show the location of inlet and outlet taps.
|| Inlet water tap is placed at the top-left of the container.

Outlet water tap is placed at the bottom-left of the container.
|-
|| Cursor on container.
|| The container is graduated and is filled with water.

The markings show from 1x 10<sup>-23</sup> Liters to 8x 10<sup>-23</sup> Liters.
|-
|| Drag the slider on the inlet water tap.

Drag the slider on the outlet water tap.
|| Drag the slider on the inlet water tap towards the right side to fill the container.

To drain the water from the container, drag the slider on the outlet water tap.
|-
|| Show salt shaker.
|| A salt shaker is placed at the top of the container.

Shake the salt dispenser to add salt to the container.
|-
|| Cursor on right panel.
|| On the right panel you will see the Salt''' '''and '''Water '''sections.
|-
|| Cursor on right panel.
|| Salt section gives information about the ions present in the container.

It shows the number of dissolved, bound and total number of ions in the container.
|-
|| Cursor on right panel.
|| The water section shows the volume of water in the container.

|-
|| Cursor on '''Reset All '''button.
|| Click on the '''Reset All '''button on the right panel.

To reset the simulation to the default parameters.
|-
|| Cursor on the water container.
|| Let us see how table salt dissolves in water.

Let the water level in the container be at the default level, 5x10<sup>-23</sup> liters mark.
|-
|| Shake the salt shaker.
|| Shake the salt shaker to add salt to the container.

|-
|| '''Slide Number 6'''

'''Solubility Product expression of NaCl'''

<sup>NaCl(s) ⇄ Na+(aq) + Cl-(aq)</sup>

<sup>K</sup><sub>sp</sub><sup> = [Na+] [Cl-]</sup>

|| Table salt is scientifically called Sodium Chloride.

It ionizes in water as sodium and chloride ions.

Here is the Solubility Product expression of NaCl

The smaller the Solubility Product, the lower the solubility.

|-
|| Cursor on sodium and chloride ions.
|| Sodium ions are represented as red spheres and chloride ions as green spheres.

Add more salt to the container and observe the solution.
|-
|| Cursor on sodium and chloride ions.
|| As soon as the salt touches the water it dissociates into sodium ions and chloride ions.
|-
|| Cursor on right panel.
|| Note the number of sodium and chloride ions in the Salt panel on the right.

They are equal in number.

The sodium chloride is neutral molecule

It has one positive sodium ion and one negative chloride ion.
|-
|| Shake the salt dispenser.

180 ions in solution, no bound ions.
|| Add more salt to the container.

Observe the right panel.

Wait for a few seconds for the solution to reach equilibrium.
|-
|| Cursor on the water container.

Shake the salt dispenser.
|| Sodium chloride is highly soluble in water.

The bound ions will be zero until it reaches the saturation level.

Add more salt until you see some bound ions in the Salt panel.
|-
|| Cursor on the right panel.
|| The salt solution has now reached saturation level.

The bound or undissolved ions are in equilibrium with the dissolved ions in solution.

Approximately 180 dissolved ions are observed.

Notice the continuous adjustment of dissolved and bound ions on the panel.
|-
|| Cursor on the water container.
|| Observe the ions in the container.

The ions continuously go back and forth from dissolved to bound state to maintain the equilibrium.

|-
|| Cursor on the right panel.
|| Molar solubility for sodium chloride can be calculated using the information in the right panel.

Solubility Product can be calculated from the molar solubility value for each salt.

|-
|| Cursor on the right panel.
|| Note the number of cations and anions at saturation state for sodium chloride.

It is 180 in 5 x 10<sup>-23 </sup>liters for sodium chloride.

|-
|| '''Slide Number 7'''

'''Calculations: Molar Solubility'''

|| This slide shows how to calculate molar solubility for sodium chloride.

|-
|| '''Slide Number 8'''

'''Calculations: Solubility Product'''

|| We can also calculate Solubility Product for sodium chloride using molar solubility values.

Please refer to additional reading material for details of calculations.

|-
|| Cursor on Simulation interface.

|| Back to the simulation.

Add more salt.

The number of bound ions increases in the solution.
|-
|| Drag the slider on the inlet tap.
|| Add some water to the container.

Observe the ions in the panel as well as in the container.
|-
|| Cursor on the simulation.
|| The number of dissolved ions increases with dilution.

This is because the bound ions now dissolve in the extra added water.

This is in accordance with Le Chatelier's principle.
|-
|| Drag the slider on the inlet tap.
|| Add more water until all the bound ions completely dissolve.
|-
|| Cursor on the simulation.
|| Please refer to the additional material link for more information on Le Chatelier's principle.
|-
|| Click the '''Reset All '''button.
|| Click the '''Reset All '''button.

Practice with a different volume of water in the container.

Observe the results.
|-
|| Click on '''Slightly Soluble Salts''' tab.
|| Next click on '''Slightly Soluble Salts''' tab.

The right panel on the screen shows a drop-down in the '''Salt''' section.
|-
|| Cursor on the right panel.
|| 6 different types of sparingly soluble salts are listed here.
|-
||
|| The rest of the simulation interface is similar to the '''Table Salt '''screen.
|-
|| Shake the salt dispenser.
|| The first salt in the list is '''Strontium Phosphate'''.

Shake the salt dispenser.

A little amount of salt is added to the container with water.

|-
|| Cursor on the right panel.
|| Notice the ratio of Strontium to Phosphate ions in the right panel.
|-
|| '''Slide Number 9'''

Solubility Product expression for Strontium phosphate.
|| This slide shows the Solubility Product expression for Strontium phosphate.

The stoichiometry is 3 is to 2 (3:2).

Therefore the strontium phosphate molecule consists of:

3 atoms of strontium and 2 units of phosphate.
|-
|| Shake the salt dispenser.

Observe the right panel.
|| Shake the salt dispenser a few more times.

You will now notice some bound strontium and phosphate ions in the container.

Observe the right panel.
|-
|| Shake the salt dispenser.

Observe the right panel.
|| Shake the salt dispenser a few more times until you see constant unbound ions in solution.

The solution is now saturated. The equilibrium is established.

At this stage, 45 strontium and 30 phosphate ions are in dissolved state .

The ratio is 3: 2
|-
|| Observe the right panel.
|| Molar solubility for salts can be calculated using the information in the right panel.

Solubility Product can be calculated from the molar solubility value for each salt.
|-
|| '''Slide Number 10'''

'''Table Calculations: Molar solubility '''

|| This slide shows how to calculate molar solubility for strontium phosphate.

|-
|| '''Slide Number 11'''

'''Table Calculations: Solubility Product'''
|| I have calculated the molar solubility and Solubility Product for strontium phosphate

Make a data table as shown here in your notebook and fill the columns.
|-
|| Cursor on the simulation interface.
|| Increase or decrease the volume of water in the container and observe the results.
|-
|| '''Slide Number 12'''

'''Assignment'''
|| You can pause the video and do the following:

Add more water to the container and observe the dissolved and bound ions in water.

Check the solubility of the salts given in the salt drop-down on the right panel.

Note the ratio of ions in each salt.

Note the number of ions at saturation for each salt.

|-
|| Click on '''Design a Salt''' tab.
|| Now click on '''Design a Salt''' tab at the top of the simulation.
|-
|| Cursor on the simulation interface.
|| Here we can creatively design a salt using the different charges for cation and anion.
|-
|| Cursor on the right panel.
|| On the right panel using the drop-down buttons select the charges of your choice.
|-
|| Select cation charge as +2 and anion as -1.
|| I will select cation charge as +2 and anion as -1.
|-
|| Select the Solubility Product as 1 x 10<sup>-19</sup>
|| I will select the Solubility Product as 1 x 10<sup>-19</sup>.
|-
|| Shake the salt dispenser.
|| Shake the salt dispenser over the container of water.

Observe the ratio of dissolved cations and anions.

We see two anions for every one cation.

The number of anions is double the number of cations.

This ratio is in accordance with the charges we selected for cation and anion for the salt.
|-
||

Select Solubility Product as 1 x 10<sup>-7</sup>.
||

Now increase the Solubility Product of the salt to 1x10<sup>-7</sup>.
|-
|| Shake the salt dispenser over the container of water.
|| Shake the salt dispenser over the container of water.

Observe the number of dissolved ions in the right panel.
|-
|| Cursor on the right panel.
|| Notice the solubility of the salt.

The number of dissolved ions is more this time.

Hence, solubility is more when Solubility Product value is more.
|-
|| '''Slide Number 13'''

'''Summary'''
|| Let us summarize.

In this tutorial we have learnt about,

*Solubility of different salts

*Created a neutral compound from anions and cations

*Equilibrium expression for dissolution of salt in water.

*Calculated the molarity of solutions

*Calculated Solubility Product of salts

|-
|| '''Slide Number 14'''

'''Summary'''
|| Application of Le Chatelier's principle to the dissolution of salts

*Designed a salt with various combinations of charges and Solubility Products.

*Used Solubility Product values to predict solubility.
|-
|| '''Slide Number 15'''

'''Assignment'''

'''Show table here.'''
||

As an assignment,

Explore more salts with various combinations of charges and Solubility Products.

Calculate the molar solubility and Solubility Product for the salts.

|-
|| '''Slide Number 16'''

'''About Spoken Tutorial Project '''
||The video at the following link

Summarises the Spoken Tutorial project

*Please download and watch it.

|-
|| '''Slide Number 17'''
'''Spoken tutorial workshops '''
||We conduct workshops using spoken tutorials and give certificates.
*For more details, please contact us.

|-
|| '''Slide Number 18'''

'''Answers for THIS Spoken Tutorial '''

Do you have questions in THIS Spoken Tutorial?

Please visit this site

Choose the minute and second where you have the question.

Explain your question briefly

The spoken tutorial project will ensure answer.

You will have to register on this website to ask questions.
|| * <div style="margin-left:1.245cm;margin-right:0cm;">Please post your timed queries in this forum.

|-
|| '''Slide Number 19'''
'''Acknowledgement '''
|| Spoken Tutorial project is funded by Ministry of Education (MoE), Govt. of India
|-
| |
|| The script for this tutorial is contributed by Snehalatha Kaliappan from IIT Bombay.

This is Vidhi Thakur, a FOSSEE

summer fellow 2022, IIT Bombay

signing off

Thank you for joining.
|-
|}

PhET-Simulations-for-Chemistry/C3/Salts-and-Solubility/English

2022-11-05T05:52:23Z

Vidhithakur:

'''Salts and Solubility '''

'''Author: Snehalatha Kaliappan'''

'''Keywords: '''Salts, sparingly soluble salts, solubility, molar solubility, solubility product, molarity, Le Chaterlier’s principle, equilibrium expression, video tutorial

{|border=1
|-
||'''Visual Cue'''
||'''Narration'''
|-
|| '''Slide Number 1'''

'''Title Slide'''
|| Welcome to this tutorial on '''Salts and Solubility'''
|-
|| '''Slide Number 2'''

'''Learning Objectives'''
|| In this tutorial, we will learn about,

*Solubility of different salts.

*Create a neutral compound from anions and cations.

*Equilibrium expression for dissolution of salt in water.

*Calculate the molarity of solutions.

*Calculate Solubility Product of the salts.

|-
|| '''Slide Number 3'''

'''Learning Objectives'''
|| Application of Le Chaterlier’s principle to the dissolution of salts

*Design a salt with various combinations of charges and Solubility Products.

*Use Solubility Product values to predict solubility.

|-
|| '''Slide Number 3'''

'''System Requirement'''
|| Here I am using

'''Windows 11 (64 bit).'''

'''Java version 1.8'''
|-
|| '''Slide Number 4'''

'''Pre-requisites'''

'''[https://spoken-tutorial.org/ https://spoken-tutorial.org]'''

|| To follow this tutorial learner should be familiar with,

topics in high school science.

Please use the link below to access the tutorials on PhET Simulations.

|-
|| '''Slide Number 5'''

'''Link for PhET simulation'''

point to

'''[https://phet.colorado.edu/en/simulations/soluble-salts]'''

|| Please use the given link to download the PhET simulation.

|-
|| '''Point to the file in Downloads folder.'''
|| I have downloaded the '''Salts & Solubility '''simulation, to my Downloads folder.
|-
|| '''Double click the file to open'''
|| To open the simulation double click on the file.
|-
|| '''Cursor on the interface.'''
|| This is the interface of '''salt and solubility simulation'''.
|-
||

Cursor moves across the tabs.
||

It has 3 tabs.
|-
|| Cursor on Table Salt interface.

|| '''Table Salt '''tab opens first by default.

The main panel shows a container with inlet and outlet water taps.
|-
|| Show the location of inlet and outlet taps.
|| Inlet water tap is placed at the top-left of the container.

Outlet water tap is placed at the bottom-left of the container.
|-
|| Cursor on container.
|| The container is graduated and is filled with water.

The markings show from 1x 10<sup>-23</sup> Liters to 8x 10<sup>-23</sup> Liters.
|-
|| Drag the slider on the inlet water tap.

Drag the slider on the outlet water tap.
|| Drag the slider on the inlet water tap towards the right side to fill the container.

To drain the water from the container, drag the slider on the outlet water tap.
|-
|| Show salt shaker.
|| A salt shaker is placed at the top of the container.

Shake the salt dispenser to add salt to the container.
|-
|| Cursor on right panel.
|| On the right panel you will see the Salt''' '''and '''Water '''sections.
|-
|| Cursor on right panel.
|| Salt section gives information about the ions present in the container.

It shows the number of dissolved, bound and total number of ions in the container.
|-
|| Cursor on right panel.
|| The water section shows the volume of water in the container.

|-
|| Cursor on '''Reset All '''button.
|| Click on the '''Reset All '''button on the right panel.

To reset the simulation to the default parameters.
|-
|| Cursor on the water container.
|| Let us see how table salt dissolves in water.

Let the water level in the container be at the default level, 5x10<sup>-23</sup> liters mark.
|-
|| Shake the salt shaker.
|| Shake the salt shaker to add salt to the container.

|-
|| '''Slide Number 6'''

'''Solubility Product expression of NaCl'''

|| Table salt is scientifically called Sodium Chloride.

It ionizes in water as sodium and chloride ions.

Here is the Solubility Product expression of NaCl

<sup>NaCl(s) <----> Na+(aq) + Cl-(aq)</sup>

<sup>K</sup><sub>sp</sub><sup> = [Na+] [Cl-]</sup>

The smaller the Solubility Product, the lower the solubility.

|-
|| Cursor on sodium and chloride ions.
|| Sodium ions are represented as red spheres and chloride ions as green spheres.

Add more salt to the container and observe the solution.
|-
|| Cursor on sodium and chloride ions.
|| As soon as the salt touches the water it dissociates into sodium ions and chloride ions.
|-
|| Cursor on right panel.
|| Note the number of sodium and chloride ions in the Salt panel on the right.

They are equal in number.

The sodium chloride is neutral molecule

It has one positive sodium ion and one negative chloride ion.
|-
|| Shake the salt dispenser.

180 ions in solution, no bound ions.
|| Add more salt to the container.

Observe the right panel.

Wait for a few seconds for the solution to reach equilibrium.
|-
|| Cursor on the water container.

Shake the salt dispenser.
|| Sodium chloride is highly soluble in water.

The bound ions will be zero until it reaches the saturation level.

Add more salt until you see some bound ions in the Salt panel.
|-
|| Cursor on the right panel.
|| The salt solution has now reached saturation level.

The bound or undissolved ions are in equilibrium with the dissolved ions in solution.

Approximately 180 dissolved ions are observed.

Notice the continuous adjustment of dissolved and bound ions on the panel.
|-
|| Cursor on the water container.
|| Observe the ions in the container.

The ions continuously go back and forth from dissolved to bound state to maintain the equilibrium.

|-
|| Cursor on the right panel.
|| Molar solubility for sodium chloride can be calculated using the information in the right panel.

Solubility Product can be calculated from the molar solubility value for each salt.

|-
|| Cursor on the right panel.
|| Note the number of cations and anions at saturation state for sodium chloride.

It is 180 in 5 x 10<sup>-23 </sup>liters for sodium chloride.

|-
|| '''Slide Number 7'''

'''Calculations: Molar Solubility'''

|| This slide shows how to calculate molar solubility for sodium chloride.

|-
|| '''Slide Number 8'''

'''Calculations: Solubility Product'''

|| We can also calculate Solubility Product for sodium chloride using molar solubility values.

Please refer to additional reading material for details of calculations.

|-
|| Cursor on Simulation interface.

|| Back to the simulation.

Add more salt.

The number of bound ions increases in the solution.
|-
|| Drag the slider on the inlet tap.
|| Add some water to the container.

Observe the ions in the panel as well as in the container.
|-
|| Cursor on the simulation.
|| The number of dissolved ions increases with dilution.

This is because the bound ions now dissolve in the extra added water.

This is in accordance with Le Chatelier's principle.
|-
|| Drag the slider on the inlet tap.
|| Add more water until all the bound ions completely dissolve.
|-
|| Cursor on the simulation.
|| Please refer to the additional material link for more information on Le Chatelier's principle.
|-
|| Click the '''Reset All '''button.
|| Click the '''Reset All '''button.

Practice with a different volume of water in the container.

Observe the results.
|-
|| Click on '''Slightly Soluble Salts''' tab.
|| Next click on '''Slightly Soluble Salts''' tab.

The right panel on the screen shows a drop-down in the '''Salt''' section.
|-
|| Cursor on the right panel.
|| 6 different types of sparingly soluble salts are listed here.
|-
||
|| The rest of the simulation interface is similar to the '''Table Salt '''screen.
|-
|| Shake the salt dispenser.
|| The first salt in the list is '''Strontium Phosphate'''.

Shake the salt dispenser.

A little amount of salt is added to the container with water.

|-
|| Cursor on the right panel.
|| Notice the ratio of Strontium to Phosphate ions in the right panel.
|-
|| '''Slide Number 9'''

Solubility Product expression for Strontium phosphate.
|| This slide shows the Solubility Product expression for Strontium phosphate.

The stoichiometry is 3 is to 2 (3:2).

Therefore the strontium phosphate molecule consists of:

3 atoms of strontium and 2 units of phosphate.
|-
|| Shake the salt dispenser.

Observe the right panel.
|| Shake the salt dispenser a few more times.

You will now notice some bound strontium and phosphate ions in the container.

Observe the right panel.
|-
|| Shake the salt dispenser.

Observe the right panel.
|| Shake the salt dispenser a few more times until you see constant unbound ions in solution.

The solution is now saturated. The equilibrium is established.

At this stage, 45 strontium and 30 phosphate ions are in dissolved state .

The ratio is 3: 2
|-
|| Observe the right panel.
|| Molar solubility for salts can be calculated using the information in the right panel.

Solubility Product can be calculated from the molar solubility value for each salt.
|-
|| '''Slide Number 10'''

'''Table Calculations: Molar solubility '''

|| This slide shows how to calculate molar solubility for strontium phosphate.

|-
|| '''Slide Number 11'''

'''Table Calculations: Solubility Product'''
|| I have calculated the molar solubility and Solubility Product for strontium phosphate

Make a data table as shown here in your notebook and fill the columns.
|-
|| Cursor on the simulation interface.
|| Increase or decrease the volume of water in the container and observe the results.
|-
|| '''Slide Number 12'''

'''Assignment'''
|| You can pause the video and do the following:

Add more water to the container and observe the dissolved and bound ions in water.

Check the solubility of the salts given in the salt drop-down on the right panel.

Note the ratio of ions in each salt.

Note the number of ions at saturation for each salt.

|-
|| Click on '''Design a Salt''' tab.
|| Now click on '''Design a Salt''' tab at the top of the simulation.
|-
|| Cursor on the simulation interface.
|| Here we can creatively design a salt using the different charges for cation and anion.
|-
|| Cursor on the right panel.
|| On the right panel using the drop-down buttons select the charges of your choice.
|-
|| Select cation charge as +2 and anion as -1.
|| I will select cation charge as +2 and anion as -1.
|-
|| Select the Solubility Product as 1 x 10<sup>-19</sup>
|| I will select the Solubility Product as 1 x 10<sup>-19</sup>.
|-
|| Shake the salt dispenser.
|| Shake the salt dispenser over the container of water.

Observe the ratio of dissolved cations and anions.

We see two anions for every one cation.

The number of anions is double the number of cations.

This ratio is in accordance with the charges we selected for cation and anion for the salt.
|-
||

Select Solubility Product as 1 x 10<sup>-7</sup>.
||

Now increase the Solubility Product of the salt to 1x10<sup>-7</sup>.
|-
|| Shake the salt dispenser over the container of water.
|| Shake the salt dispenser over the container of water.

Observe the number of dissolved ions in the right panel.
|-
|| Cursor on the right panel.
|| Notice the solubility of the salt.

The number of dissolved ions is more this time.

Hence, solubility is more when Solubility Product value is more.
|-
|| '''Slide Number 13'''

'''Summary'''
|| Let us summarize.

In this tutorial we have learnt about,

*Solubility of different salts

*Created a neutral compound from anions and cations

*Equilibrium expression for dissolution of salt in water.

*Calculated the molarity of solutions

*Calculated Solubility Product of salts

|-
|| '''Slide Number 14'''

'''Summary'''
|| Application of Le Chatelier's principle to the dissolution of salts

*Designed a salt with various combinations of charges and Solubility Products.

*Used Solubility Product values to predict solubility.
|-
|| '''Slide Number 15'''

'''Assignment'''

'''Show table here.'''
||

As an assignment,

Explore more salts with various combinations of charges and Solubility Products.

Calculate the molar solubility and Solubility Product for the salts.

|-
|| '''Slide''': 14

'''About Spoken Tutorial Project '''
||The video at the following link

Summarises the Spoken Tutorial project

*Please download and watch it.

|-
|| '''Slide''': 15

'''Spoken tutorial workshops '''
||We conduct workshops using spoken tutorials and give certificates.
*For more details, please contact us.

|-
|| '''Slide''': 16

'''Answers for THIS Spoken Tutorial '''

Do you have questions in THIS Spoken Tutorial?

Please visit this site

Choose the minute and second where you have the question.

Explain your question briefly

The spoken tutorial project will ensure answer.

You will have to register on this website to ask questions.
|| * <div style="margin-left:1.245cm;margin-right:0cm;">Please post your timed queries in this forum.

|-
|| '''Slide''': 18

'''Acknowledgement '''
|| Spoken Tutorial project is funded by Ministry of Education (MoE), Govt. of India
|-
| |
|| The script for this tutorial is contributed by Snehalatha Kaliappan from IIT Bombay.

This is Vidhi Thakur, a FOSSEE

summer fellow 2022, IIT Bombay

signing off

Thank you for joining.
|-
|}

PhET-Simulations-for-Chemistry/C3/Salts-and-Solubility/English

2022-11-05T05:30:35Z

Vidhithakur: Created page with "'''Salts and Solubility ''' '''Author: Snehalatha Kaliappan''' '''Keywords: '''Salts, sparingly soluble salts, solubility, molar solubility, solubility product, molarity, L..."

'''Salts and Solubility '''

'''Author: Snehalatha Kaliappan'''

'''Keywords: '''Salts, sparingly soluble salts, solubility, molar solubility, solubility product, molarity, Le Chaterlier’s principle, equilibrium expression, video tutorial

{|border=1
|-
||'''Visual Cue'''
||'''Narration'''
|-
|| '''Slide Number 1'''

'''Title Slide'''
|| Welcome to this tutorial on '''Salts and Solubility'''
|-
|| '''Slide Number 2'''

'''Learning Objectives'''
|| In this tutorial, we will learn about,

*Solubility of different salts.

*Create a neutral compound from anions and cations.

*Equilibrium expression for dissolution of salt in water.

*Calculate the molarity of solutions.

*Calculate Solubility Product of the salts.

|-
|| '''Slide Number 3'''

'''Learning Objectives'''
|| Application of Le Chaterlier’s principle to the dissolution of salts

*Design a salt with various combinations of charges and Solubility Products.

*Use Solubility Product values to predict solubility.

|-
|| '''Slide Number 3'''

'''System Requirement'''
|| Here I am using

'''Windows 11 (64 bit).'''

'''Java version 1.8'''
|-
|| '''Slide Number 4'''

'''Pre-requisites'''

''' '''

[https://spoken-tutorial.org/ https://spoken-tutorial.org]

|| To follow this tutorial learner should be familiar with,

topics in high school science.

Please use the link below to access the tutorials on PhET Simulations.

|-
|| '''Slide Number 5'''

'''Link for PhET simulation'''

point to

https://phet.colorado.edu/en/simulations/soluble-salts
|| Please use the given link to download the PhET simulation.

'''https://phet.colorado.edu/en/simulations/soluble-salts'''

|-
|| '''Point to the file in Downloads folder.'''
|| I have downloaded the '''Salts & Solubility '''simulation, to my Downloads folder.
|-
|| '''Double click the file to open'''
|| To open the simulation double click on the file.
|-
|| '''Cursor on the interface.'''
|| This is the interface of '''salt and solubility simulation'''.
|-
||

Cursor moves across the tabs.
||

It has 3 tabs.
|-
|| Cursor on Table Salt interface.

|| '''Table Salt '''tab opens first by default.

The main panel shows a container with inlet and outlet water taps.
|-
|| Show the location of inlet and outlet taps.
|| Inlet water tap is placed at the top-left of the container.

Outlet water tap is placed at the bottom-left of the container.
|-
|| Cursor on container.
|| The container is graduated and is filled with water.

The markings show from 1x 10<sup>-23</sup> Liters to 8x 10<sup>-23</sup> Liters.
|-
|| Drag the slider on the inlet water tap.

Drag the slider on the outlet water tap.
|| Drag the slider on the inlet water tap towards the right side to fill the container.

To drain the water from the container, drag the slider on the outlet water tap.
|-
|| Show salt shaker.
|| A salt shaker is placed at the top of the container.

Shake the salt dispenser to add salt to the container.
|-
|| Cursor on right panel.
|| On the right panel you will see the Salt''' '''and '''Water '''sections.
|-
|| Cursor on right panel.
|| Salt section gives information about the ions present in the container.

It shows the number of dissolved, bound and total number of ions in the container.
|-
|| Cursor on right panel.
|| The water section shows the volume of water in the container.

|-
|| Cursor on '''Reset All '''button.
|| Click on the '''Reset All '''button on the right panel.

To reset the simulation to the default parameters.
|-
|| Cursor on the water container.
|| Let us see how table salt dissolves in water.

Let the water level in the container be at the default level, 5x10<sup>-23</sup> liters mark.
|-
|| Shake the salt shaker.
|| Shake the salt shaker to add salt to the container.

|-
|| '''Slide Number 6'''

'''Solubility Product expression of NaCl'''

|| Table salt is scientifically called Sodium Chloride.

It ionizes in water as sodium and chloride ions.

Here is the Solubility Product expression of NaCl

<sup>NaCl(s) <----> Na+(aq) + Cl-(aq)</sup>

<sup>K</sup><sub>sp</sub><sup> = [Na+] [Cl-]</sup>

The smaller the Solubility Product, the lower the solubility.

|-
|| Cursor on sodium and chloride ions.
|| Sodium ions are represented as red spheres and chloride ions as green spheres.

Add more salt to the container and observe the solution.
|-
|| Cursor on sodium and chloride ions.
|| As soon as the salt touches the water it dissociates into sodium ions and chloride ions.
|-
|| Cursor on right panel.
|| Note the number of sodium and chloride ions in the Salt panel on the right.

They are equal in number.

The sodium chloride is neutral molecule

It has one positive sodium ion and one negative chloride ion.
|-
|| Shake the salt dispenser.

180 ions in solution, no bound ions.
|| Add more salt to the container.

Observe the right panel.

Wait for a few seconds for the solution to reach equilibrium.
|-
|| Cursor on the water container.

Shake the salt dispenser.
|| Sodium chloride is highly soluble in water.

The bound ions will be zero until it reaches the saturation level.

Add more salt until you see some bound ions in the Salt panel.
|-
|| Cursor on the right panel.
|| The salt solution has now reached saturation level.

The bound or undissolved ions are in equilibrium with the dissolved ions in solution.

Approximately 180 dissolved ions are observed.

Notice the continuous adjustment of dissolved and bound ions on the panel.
|-
|| Cursor on the water container.
|| Observe the ions in the container.

The ions continuously go back and forth from dissolved to bound state to maintain the equilibrium.

|-
|| Cursor on the right panel.
|| Molar solubility for sodium chloride can be calculated using the information in the right panel.

Solubility Product can be calculated from the molar solubility value for each salt.

|-
|| Cursor on the right panel.
|| Note the number of cations and anions at saturation state for sodium chloride.

It is 180 in 5 x 10<sup>-23 </sup>liters for sodium chloride.

|-
|| '''Slide Number 7'''

'''Calculations: Molar Solubility'''

|| This slide shows how to calculate molar solubility for sodium chloride.

|-
|| '''Slide Number 8'''

'''Calculations: Solubility Product'''

|| We can also calculate Solubility Product for sodium chloride using molar solubility values.

Please refer to additional reading material for details of calculations.

|-
|| Cursor on Simulation interface.

|| Back to the simulation.

Add more salt.

The number of bound ions increases in the solution.
|-
|| Drag the slider on the inlet tap.
|| Add some water to the container.

Observe the ions in the panel as well as in the container.
|-
|| Cursor on the simulation.
|| The number of dissolved ions increases with dilution.

This is because the bound ions now dissolve in the extra added water.

This is in accordance with Le Chatelier's principle.
|-
|| Drag the slider on the inlet tap.
|| Add more water until all the bound ions completely dissolve.
|-
|| Cursor on the simulation.
|| Please refer to the additional material link for more information on Le Chatelier's principle.
|-
|| Click the '''Reset All '''button.
|| Click the '''Reset All '''button.

Practice with a different volume of water in the container.

Observe the results.
|-
|| Click on '''Slightly Soluble Salts''' tab.
|| Next click on '''Slightly Soluble Salts''' tab.

The right panel on the screen shows a drop-down in the '''Salt''' section.
|-
|| Cursor on the right panel.
|| 6 different types of sparingly soluble salts are listed here.
|-
||
|| The rest of the simulation interface is similar to the '''Table Salt '''screen.
|-
|| Shake the salt dispenser.
|| The first salt in the list is '''Strontium Phosphate'''.

Shake the salt dispenser.

A little amount of salt is added to the container with water.

|-
|| Cursor on the right panel.
|| Notice the ratio of Strontium to Phosphate ions in the right panel.
|-
|| '''Slide Number 9'''

Solubility Product expression for Strontium phosphate.
|| This slide shows the Solubility Product expression for Strontium phosphate.

The stoichiometry is 3 is to 2 (3:2).

Therefore the strontium phosphate molecule consists of:

3 atoms of strontium and 2 units of phosphate.
|-
|| Shake the salt dispenser.

Observe the right panel.
|| Shake the salt dispenser a few more times.

You will now notice some bound strontium and phosphate ions in the container.

Observe the right panel.
|-
|| Shake the salt dispenser.

Observe the right panel.
|| Shake the salt dispenser a few more times until you see constant unbound ions in solution.

The solution is now saturated. The equilibrium is established.

At this stage, 45 strontium and 30 phosphate ions are in dissolved state .

The ratio is 3: 2
|-
|| Observe the right panel.
|| Molar solubility for salts can be calculated using the information in the right panel.

Solubility Product can be calculated from the molar solubility value for each salt.
|-
|| '''Slide Number 10'''

'''Table Calculations: Molar solubility '''

|| This slide shows how to calculate molar solubility for strontium phosphate.

|-
|| '''Slide Number 11'''

'''Table Calculations: Solubility Product'''
|| I have calculated the molar solubility and Solubility Product for strontium phosphate

Make a data table as shown here in your notebook and fill the columns.
|-
|| Cursor on the simulation interface.
|| Increase or decrease the volume of water in the container and observe the results.
|-
|| '''Slide Number 12'''

'''Assignment'''
|| You can pause the video and do the following:

Add more water to the container and observe the dissolved and bound ions in water.

Check the solubility of the salts given in the salt drop-down on the right panel.

Note the ratio of ions in each salt.

Note the number of ions at saturation for each salt.

|-
|| Click on '''Design a Salt''' tab.
|| Now click on '''Design a Salt''' tab at the top of the simulation.
|-
|| Cursor on the simulation interface.
|| Here we can creatively design a salt using the different charges for cation and anion.
|-
|| Cursor on the right panel.
|| On the right panel using the drop-down buttons select the charges of your choice.
|-
|| Select cation charge as +2 and anion as -1.
|| I will select cation charge as +2 and anion as -1.
|-
|| Select the Solubility Product as 1 x 10<sup>-19</sup>
|| I will select the Solubility Product as 1 x 10<sup>-19</sup>.
|-
|| Shake the salt dispenser.
|| Shake the salt dispenser over the container of water.

Observe the ratio of dissolved cations and anions.

We see two anions for every one cation.

The number of anions is double the number of cations.

This ratio is in accordance with the charges we selected for cation and anion for the salt.
|-
||

Select Solubility Product as 1 x 10<sup>-7</sup>.
||

Now increase the Solubility Product of the salt to 1x10<sup>-7</sup>.
|-
|| Shake the salt dispenser over the container of water.
|| Shake the salt dispenser over the container of water.

Observe the number of dissolved ions in the right panel.
|-
|| Cursor on the right panel.
|| Notice the solubility of the salt.

The number of dissolved ions is more this time.

Hence, solubility is more when Solubility Product value is more.
|-
|| '''Slide Number 13'''

'''Summary'''
|| Let us summarize.

In this tutorial we have learnt about,

*Solubility of different salts

*Created a neutral compound from anions and cations

*Equilibrium expression for dissolution of salt in water.

*Calculated the molarity of solutions

*Calculated Solubility Product of salts

|-
|| '''Slide Number 14'''

'''Summary'''
|| Application of Le Chatelier's principle to the dissolution of salts

*Designed a salt with various combinations of charges and Solubility Products.

*Used Solubility Product values to predict solubility.
|-
|| '''Slide Number 15'''

'''Assignment'''

'''Show table here.'''
||

As an assignment,

Explore more salts with various combinations of charges and Solubility Products.

Calculate the molar solubility and Solubility Product for the salts.

|-
|| '''Slide''': 14

'''About Spoken Tutorial Project '''
||The video at the following link

Summarises the Spoken Tutorial project

*Please download and watch it.

|-
|| '''Slide''': 15

'''Spoken tutorial workshops '''
||We conduct workshops using spoken tutorials and give certificates.
*For more details, please contact us.

|-
|| '''Slide''': 16

'''Answers for THIS Spoken Tutorial '''

Do you have questions in THIS Spoken Tutorial?

Please visit this site

Choose the minute and second where you have the question.

Explain your question briefly

The spoken tutorial project will ensure answer.

You will have to register on this website to ask questions.
|| * <div style="margin-left:1.245cm;margin-right:0cm;">Please post your timed queries in this forum.

|-
|| '''Slide''': 18

'''Acknowledgement '''
|| Spoken Tutorial project is funded by Ministry of Education (MoE), Govt. of India
|-
| |
|| The script for this tutorial is contributed by Snehalatha Kaliappan from IIT Bombay.

This is Vidhi Thakur, a FOSSEE

summer fellow 2022, IIT Bombay

signing off

Thank you for joining.
|-
|}

PhET-Simulations-for-Chemistry/C3/Semicondutors/English

2022-11-02T15:57:36Z

'''Semiconductors'''

'''Author: Vidhi Thakur'''

'''Keywords: PhET simulation''', dopants, diode, valence band, conduction band, donor, acceptor, depletion region '''video tutorial.'''

{|border=1
|-
||'''Visual Cue'''
||''' Narration '''
|-
|| '''Slide Number 1'''

'''Title Slide'''
|| Welcome to this spoken tutorial on '''Semiconductors'''.
|-
|| '''Slide Number 2'''

'''Learning Objectives'''

|| In this tutorial, we will learn,

* How a battery acts as a driving force in a circuit.
* To add dopants to move the electrons in the circuit.
* How the dopants change energy levels in a semiconductor
* Why a pn junction acts as a diode
* Why a depletion region does not allow current to flow.

|-
|| '''Slide Number 3'''

'''System Requirement'''
|| Here I am using

'''Windows 11 (64 bit).'''

'''Java Version 1.8'''
|-
||'''Slide Number 4'''

'''Pre-requisites'''
'''https://spoken-tutorial.org'''
||To follow this tutorial the learner should be familiar with topics in high school science.
Please use the link below to access the tutorials on PhET simulations.
|-
||'''Slide Number 5'''

'''Link for PhET simulation'''

point to

'''https://phet.colorado.edu/en/simulations/conductivity/about'''
|| Please use the given link to download the PhET simulation.

'''https://phet.colorado.edu/en/simulations/semiconductor/about'''
|-
||'''Point to the file in the Downloads folder'''.
|| I have downloaded the '''Semiconductors simulation '''to my '''Downloads''' folder.
|-
||'''Double click the file to open'''
|| To open the simulation double click on the file.

|-
||'''Cursor on the interface.'''
|| This is the interface of '''Semiconductors simulation.'''
|-
||Cursor on '''main panel'''.

Cursor on '''input box.'''

Cursor on '''electrons.'''

|| The main panel consists of a circuit.

The circuit has a battery with the box to input the voltage.

'''Electrons''' are represented as blue spheres in the circuit.
|-
|| Cursor on '''dopants.'''

|| Point to the P Type and N Type dopants at the bottom.
A dopant is an impurity added to semiconductors to modify their conductivity.

At the bottom right P-type dopant is represented as '''red''' spheres and N-type as '''green''' spheres.

A P Type dopant is represented as '''red''' spheres and N Type as '''green''' spheres.

P-type dopant is with more holes, whereas n-type dopant is with more electrons.

|-
|| Cursor on '''dopant.'''

Cursor on '''valence band.'''
|| An electrode is connected to each dopant.

It expands into bands represented as '''yellow rectangles''' on the left panel.

The low energy band is the''' valence''' band.

It is filled with blue spheres as electrons and plus signs as holes.

|-
||

Cursor on '''conduction''' band.
|| The high energy band is the '''conduction''' band.

In semiconductors the gap between the bands is small.

'''Internal force '''arrow gives us the direction of the internal force.

'''Battery force '''arrow''' '''gives us the direction of battery force.
|-
|| Cursor on right panel.

Point to '''one(1) '''Segment.

'''Two(2)''' Segments.

|| On the right panel the '''Segments''' section is present.

It consists of one and two as options.

The''' one(1) '''Segment provides space for one dopant only.

The '''two(2)''' Segments provide space for two segments.

|-
|| Click on segment '''one'''.

Cursor on bands.

|| Let us first select segment one(1).

Here only one segment is present.

The electrode attached to the dopant expands into bands with electrons and holes.

Lower energy band is the valence band with low energy.

The higher energy band is the conduction band with high energy.

|-
|| Drag and add '''P-type''' in space in the bottom of the circuit.

Click on the up arrow till '''4V'''.

Cursor on circuit diagram.
|| Let’s drag and place a '''P-type '''dopant to fill in the purple space in the circuit.

Increase the voltage to '''4 volts''' and observe the movement of electrons in the circuit.

Current flows in the circuit with low energy from left-right.
|-
|| Click on down arrow till '''-4V.'''
|| Now let us decrease the voltage to''' -4 volts'''.

This way we change the terminals of the battery in the opposite direction.

There is a flow of current in the right-left direction in the circuit.

Changing the terminals, changes the direction of potential difference.

Hence direction of flow of current changes.

|-
|| Click on '''Clear Dopants'''.

Drag and add '''N-type''' dopant and click up arrow till 4V.

|| Let us clear dopants now.

Add N-type dopant to the space and increase the voltage to '''4 volts'''.

Since N-type dopants have more electrons they are known as '''donors'''.

The flow of current is from left to right in the conduction band at high energy.

|-
||

Click the down arrow till -4V.

||

Now let us change the voltage to''' -4 ''', that is. change the terminal of the battery.

This time flow of current is in the right-left''' '''direction

in the conduction band.

|-
|| Click on '''two''' segment.

Drag and add '''P-type''' dopant in the left space.

Click the arrow till 4V.

Cursor on internal force and battery force.
|| Now let us select Segments '''two(2)'''.

Drag and add '''P-type''' dopant in the left space and increase the voltage to 4 volts.

Note that electrons and holes in the valence band of the left segment disappear.

This is because p-type dopant is an acceptor.

Internal force is zero and battery force is from left to right.

So, there is no flow of current in the circuit.

|-
|| Drag and add an '''N-type''' dopant in the right space.

Cursor on battery.

|| Let us drag and add an N-type dopant in the right space.

Such diode formation is known as '''pn''' junction diode.

Here the positive terminal of the battery is connected to N-type.

Negative terminal is connected to the P-type.

Such arrangement is known as '''reversed bias.'''

|-
|| Cursor on valence band and conduction band.
|| Empty space is filled by electrons in the '''P-type''' dopant.

And holes occupy the conduction band of '''N-type''' dopant.

The direction of internal force, and battery force, are in the same''' '''direction.

Hence a more resistive thicker '''depletion''' region is formed.

This is due to the diffusion of carriers across the junction of the pn diode.

So, no flow of current is observed.

|-
|| Click on down arrow till '''-4V'''.

Cursor on battery and internal force.

Cursor on battery.
|| Now let us slowly change the voltage to '''-4 Volts'''.

Notice that decrease in voltage decreases the size of the battery force arrow.

At -4 Volts the battery force changes the direction and internal force becomes zero.

At -4 Volts, P-type dopant is connected to the positive terminal and vice-versa.

Hence it is '''forward biased''', so the depletion region is thinner here.

So, current flow is seen from N-type to P-type '''dopant '''in''' '''right-left direction.

|-
|| Click on '''Clear Dopants'''.

Drag and add '''N-type''' dopant in left space and click up arrow till 4V.

Cursor on battery and internal force.
|| Now let”s clear the '''dopants'''.

Drag and add '''N-type''' dopant in the left space and increase the voltage to '''4 Volts'''.

Electrons and holes are visible in the left segment as N-type dopants are donors.

'''Internal''' '''force''' is zero and battery force is in the right direction.

So, there is no flow of current,''' '''

|-
|| Drag and add a P-type dopant in the right space.

Cursor on battery

|| Let us drag and add '''P-type '''dopant in the right segment.

Such diode formation is known as '''pn junction diode'''.

Here, positive terminal is connected to P-type and negative terminal to N-type.

Such an arrangement is known as''' forward bias.'''

Flow of current is seen from N-type to P-type dopant from left to right direction.

Battery force is also in the same direction.
|-
|| Click on down arrow till '''-4V'''.

|| I will now change the voltage to''' -4 Volts'''.

The electrons in the left segment of the conduction band disappear.

Only holes are left.

Internal force and battery force are in the left direction.

So, we see no flow of current.

|-
|| '''Slide Number 11'''

'''Summary'''
|| With this we come to the end of this tutorial.

Let's summarise.

In this tutorial we have learnt,* How a battery acts as a driving force in a circuit.
* To add dopants to move the electrons in the circuit.
* How the dopants change energy levels in a semiconductor
* Why a pn junction acts as a diode
* Why a depletion region does not allow current to flow.

|-
|| '''Slide Number 12'''

'''Assignment'''
||

As an assignment,

Make various combinations of dopants at different voltages and record the observations.

|-
|| '''Slide''': 13

'''About Spoken Tutorial Project '''
||The video at the following link summarizes the Spoken Tutorial project.
* Please download and watch it.

|-
|| '''Slide''': 14

'''Spoken tutorial workshops '''
||We conduct workshops using spoken tutorials and give certificates.
* For more details, please contact us.

|-
|| '''Slide''': 15

'''Answers for THIS Spoken Tutorial '''

Do you have questions in THIS Spoken Tutorial?

Please visit this site

Choose the minute and second where you have the question.

Explain your question briefly

The spoken tutorial project will ensure answer.

You will have to register on this website to ask questions.
|| * <div style="margin-left:1.245cm;margin-right:0cm;">Please post your timed queries in this forum.

|-
|| '''Slide''': 17

'''Forum '''
||The Spoken Tutorial forum is for specific questions on this tutorial.
* Please do not post unrelated and general questions on them.
* This will help reduce the clutter.
* With less clutter, we can use these discussions as instructional material.

|-
|| '''Slide''': 16

'''Acknowledgement '''
|| Spoken Tutorial project is funded by the Ministry of Education (MoE), Govt. of India
|-
||
||This is Vidhi Thakur, a FOSSEE
* summer fellow 2022, IIT Bombay
* signing off

Thank you for joining.
|-
|}

<div style="margin-left:0.811cm;margin-right:0cm;">

PhET-Simulations-for-Chemistry/C2/Conductivity/English

2022-10-21T06:35:10Z

Vidhithakur: Created page with " '''Conductivity''' '''Author: Vidhi Thakur''' '''Keywords: PhET simulation,''' '''Conductivity, battery, metals, plastic, photoconductor, valence band, conduction band, b..."

'''Conductivity'''

'''Author: Vidhi Thakur'''

'''Keywords: PhET simulation,''' '''Conductivity, battery, metals, plastic, photoconductor, valence band, conduction band, band gap, spoken tutorial, video tutorial.'''

{|border=1
||'''Visual Cue'''
||'''Narration'''
|-
|'''Slide Number 1'''

'''Title Slide'''
||Welcome to this spoken tutorial on '''Conductivity.'''
|-
||'''Slide Number 2'''

'''Learning Objectives'''

||In this tutorial, we will learn how,

* Change in voltage makes the electrons move in the circuit.

* Large band gap in plastics do not allow conductivity.

* Shining light on a photoconductor causes it to conduct electricity.
|-
||'''Slide Number 3'''

'''System Requirement'''
||Here I am using

'''Windows 11 (64 bit)'''.

'''Java Version 1.8'''.

|-
||'''Slide Number 4'''

'''Pre-requisites'''

'''https://spoken-tutorial.org'''
|| To follow this tutorial, learner should be familiar with topics in high school science.

Please use the link below to access the tutorials on PhET simulations.
|-
|| '''Slide Number 5'''

'''Link for PhET simulation'''

point to

'''https://phet.colorado.edu/en/simulations/conductivity/about'''
|| Please use the given link to download the PhET simulation.

'''https://phet.colorado.edu/en/simulations/conductivity/about'''

|-
|| '''Point to the file in the Downloads folder'''.
|| I have downloaded the '''Conductivity simulation '''to my '''Downloads''' folder.
|-
|| '''Double click the file to open'''
|| To open the simulation double click on the file.

|-
|| '''Cursor on the interface.'''
|| This is the interface of '''Conductivity simulation.'''
|-
|| Cursor on main panel.

Cursor on input box.

Cursor on electrons.

Cursor on the block.

|| The main panel consists of a circuit.

The circuit has a battery with a box to input the voltage.

Electrons represented as blue spheres are seen throughout the circuit.

A block of material is attached to the circuit at the bottom of the simulation.
|-
|| Cursor on left panel.

|| The expanded rectangle is divided into two bands.

Low energy band is valence band and high energy band is conduction band.

The material conducts electricity when electrons are present in the conduction band.

The gap between the two bands is known as bandgap.

We can see that by default all electrons are in the low energy state.

|-
|| Cursor on Materials.

Cursor on shine the light.

|| On the right panel we can see the Materials section.

It has Metal, Plastic, and Photoconductor radio buttons.

On the right panel t he â€œShine the lightâ€ option is available.

|-
|| Cursor on torch.

|| At the bottom, we have a torch to shine light.

|-
||

Click on up arrow on battery voltage box till 0.5 volts.

|| Let us leave the default selection of material as Metal.

Click the up arrow in the battery voltage box to increase the voltage to 0.2 volts.

Observe the movement of electrons in the circuit.

It means current is flowing through the circuit.

Observe the movement of electrons in the valence band.

|-
|| Click on the Pause button.
|| Let us now pause the simulation.
|-
||

Click the play button.

Click the up arrow button of Battery Voltage
to 0.5 V.
|| This simulation helps to understand the concept of conductivity.

Observe that electrons are present in the circuit, but are not moving.

Now click the '''Play''' button.

The electrons start moving, as we increase the voltage.

|-
|| Click the up arrow button of Battery Voltage to 2 V.

|| Letâ€™s increase the voltage to 2 volts and observe.

As voltage increases the potential difference between the terminals increases.

The electrons now move faster and also move to higher energy levels.
|-
| style="background-color:transparent;border-top:1pt solid #000000;border-bottom:0.5pt solid #000000;border-left:0.5pt solid #000000;border-right:none;padding-top:0cm;padding-bottom:0cm;padding-left:0.092cm;padding-right:| Cursor on left panel.

| | The gap between the valence band and the conduction band is negligible in metals.

So they overlap each other.

This makes metals good conductors of electricity.
|-
| style="background-color:transparent;border-top:1pt solid #000000;border-bottom:0.5pt solid #000000;border-left:0.5pt solid #000000;border-right:none;padding-top:0cm;padding-bottom:0cm;padding-left:0.092cm;padding-right:| Click on the Plastic radio button.

Point to band gap in the left panel.

Point to Voltage box: 2 V.

Click the '''Shine The Light '''checkbox.
| | Let us change the material to Plastic.

Observe that the energy gap between the two bands has increased.

We do not see the movement of electrons, even at high voltage.

Now let us click the '''Shine The Light '''checkbox.

Observe that even after shining light electrons are not moving.

|-
| | Cursor on left panel.

| | The band gap for plastic is very high.

So current does not flow in the circuit even after shining the light.

Hence Plastic is a non-conductor.
|-
| | Uncheck the '''Shine The Light''' check box.

| | Let us uncheck the '''Shine The Light''' check box.
|-
| | Click on the Photoconductor radio button.

Point to Voltage box: 2 V.

Click the Shine The Light check box.

Point to the movement of electrons.

Point to the electrons in the higher energy level.

| | Let us change the material to Photoconductor.

Even at high voltage no movement of electrons is seen.

Let us shine the light now.

We can now see the movement of electrons as light strikes the photoconductor.

Observe that some electrons excite to the higher energy band.

|-
| | Cursor on Left panel.
| | Band gap for a photoconductor is less than plastic and more than metal.

Hence when light strikes the material it excites electrons to high energy levels.

This intermediate material is a semiconductor with a small band gap.

Semiconductors conduct electricity in the presence of light, heat and impurities.
|-
| |
| | With this we come to the end of this tutorial.

Let's summarise.
|-
| | '''Slide Number 11'''

'''Summary'''
| | In this tutorial we have learnt how,

<div style="margin-left:1.27cm;margin-right:0cm;">Change in voltage makes the electrons move in the circuit.</div>
<div style="margin-left:1.27cm;margin-right:0cm;">Large band gap in plastics do not allow conductivity.</div>
<div style="margin-left:1.27cm;margin-right:0cm;">S<span style="background-color:#ffffff;">hining light on a photoconductor causes it to conduct electricity.</div>

|-
| | '''Slide Number 12'''

'''Assignment'''
| | Here is an assignment for you.

Check if,

<div style="margin-left:1.27cm;margin-right:0cm;">The conductivity of a metal changes when light is shined.</div>
<div style="margin-left:1.27cm;margin-right:0cm;">Photoconductors conduct electricity when battery voltage is decreased.</div>

|-
| | '''Slide''': 13

'''About Spoken Tutorial Project '''
| | The video at the following link summarizes the Spoken Tutorial project.

Please download and watch it.
|-
| | '''Slide''': 14

'''Spoken tutorial workshops '''
| | We conduct workshops using spoken tutorials and give certificates.

For more details, please contact us.
|-
| | '''Slide''': 15

'''Answers for THIS Spoken Tutorial '''

Do you have questions in THIS Spoken Tutorial?

Please visit this site

Choose the minute and second where you have the question.

Explain your question briefly

The spoken tutorial project will ensure an answer.

You will have to register on this website to ask questions.
| | Please post your timed queries in this forum.
|-
| | '''Slide''': 16

'''Acknowledgement '''
| | Spoken Tutorial project is funded by the Ministry of Education (MoE), Govt. of India
|-
| |
| | This is Vidhi Thakur, a FOSSEE summer fellow 2022, IIT Bombay signing off.

Thank you for joining.

|-
|}

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