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

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.

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	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 = 1.72 M(molar)
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.	* 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.