ChemCollective-Virtual-Labs/C2/Effect-of-temperature-on-solubility/English - Revision history

Madhurig at 06:25, 13 January 2017

2017-01-13T06:25:57Z

Snehalathak at 05:59, 13 January 2017

2017-01-13T05:59:34Z

Snehalathak at 05:50, 13 January 2017

2017-01-13T05:50:36Z

Madhurig at 11:53, 12 January 2017

2017-01-12T11:53:13Z

Madhurig: Created page with "{| border=1 ||'''Visual Cue''' ||'''Narration''' |- ||'''Slide Number 1''' '''Title Slide''' ||Hello everyone. Welcome to this tutorial on '''Effect of Temperature on Solubi..."

2017-01-12T11:07:01Z

Created page with "{| border=1 ||'''Visual Cue''' ||'''Narration''' |- ||'''Slide Number 1''' '''Title Slide''' ||Hello everyone. Welcome to this tutorial on '''Effect of Temperature on Solubi..."

New page

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

'''Title Slide'''
||Hello everyone.

Welcome to this tutorial on '''Effect of Temperature on Solubility''' using '''Vlabs'''.
|-
||'''Slide Number 2'''

'''Learning Objectives'''
||
In this tutorial, we will learn

About solubility of salts with temperature.

Check if solubility is exothermic or endothermic.

Study the relationship between solubility and heat transfer.
|-
||'''Slide Number 3'''

'''Pre-requisites'''

'''www.spoken-tutorial.org'''
||To follow this tutorial, you should be familiar with

'''ChemCollective Vlabs''' interface.

If not for relevant tutorials please visit our website.
|-
||'''Slide Number 4'''

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

Mac OS version 10.10.5

ChemCollective Vlabs version 2.1.0

Java version 8
|-
||Point to window
||Here I have opened a '''virtual chemistry lab''' application window.
|-
||Go to '''File'''->'''Load homework''' option.

Select '''Solubility and Solids'''.
Click on '''Temperature and solubility of salts'''.
||Go to '''File'''->'''Load homework''' option.

Select '''Solubility and Solids'''.
Click on '''Temperature and solubility of salts''' option.
|-
||Click on problem description
||Click on problem description in the stockroom explorer.
|-
||Point to '''problem description'''.
||Please pause the video here and read the problem description.

Resume the video once you finish reading.
|-
||Cursor on the window
||The problem has 3 sections.

In the First section: Check solubilities of '''Potassium chloride''' and '''Cerium(III)sulphate''' with temperature.

In the Second section: Observe whether dissolution of '''Potassium chloride''' and '''Cerium sulphate''' is exothermic or endothermic.

In the Third section: we have to explain the observations in section 1 and 2 based on a chemical principle.

|-
||Go back to '''workbench'''
||Click on '''Workbench'''.

Let us select required chemicals and apparatus for this experiment.
|-
||From the '''Stockroom explorer''',

Click on '''Potassium chloride''', '''Ce2(SO4)3''' and '''distilled water''' icons.
||From the '''Stockroom explorer''',
Click on '''Potassium chloride,Cerius sulfate''' and '''Distilled water''' icons.
|-
||Click on '''glassware''' icon. Select 50 mL '''Graduated Cylinder'''.
||Click on '''glassware''' icon.

Select 50 mL '''Graduated Cylinder'''.
|-
||Click on '''glassware''' icon.

Select 250 mL '''Erlenmeyer Flask'''.
||Again click on '''glassware''' icon.

Select 250 mL '''Erlenmeyer Flask'''.
|-
||Right-click, select '''Duplicate''' option from the '''context menu'''.
||We need two copies of 250 mL '''Erlenmeyer Flasks'''.

Use '''Duplicate''' option from the '''context menu''' to make the copies.
|-
||Click on '''select tools''' icon. Select '''Scale''' and '''weighing boat'''.
||Click on '''select tools''' icon.

Select '''Scale''' and '''Weighing boat'''.
|-
||Right-click, select '''Duplicate''' option from the '''context''' menu.
||We need two copies of '''Weighing boats'''.

Again use '''Duplicate''' option from the '''context menu'''.
|-
||Right-click, select '''Rename''' option from the context menu.
||Use '''context menu''' and rename the '''Erlenmeyer Flasks''' as 1 and 2.

Similarly rename the '''Weighing boats''' as 1 and 2.
|-
||Drag '''weighing boats''' and '''Erlenmeyer Flasks''' to each corner on the workbench.
||Now place each set of apparatus separately on the '''workbench'''.
|-
||Drag the '''distilled water''' tank over to '''graduated cylinder'''.

In the '''transfer amount input bar''', Type 50. Click on '''Pour'''.

Keep the '''distilled water''' aside.
||Drag the '''Distilled water''' tank over to '''graduated cylinder'''.

In the '''Transfer amount input bar''', type 50.
Click on '''Pour'''.

Keep the '''Distilled water''' aside.
|-
||Drag and place the '''graduated cylinder''' over '''flask 1'''.

In the '''transfer amount input bar''', Type 50. Click on '''pour'''.

Keep the '''graduated cylinder''' aside.
||Transfer 50 mL of '''Distilled water''' to flask 1 using '''Precise Transfer'''.

Keep the '''graduated cylinder''' aside.
|-
||Drag the weighing boat 1 and place it on the scale.

Click on TARE.
||Drag the '''weighing boat 1''' and place it on the '''scale'''.

Click on '''TARE'''.
|-
||Drag the '''potassium chloride''' bottle over to '''weighing boat'''.

Type 5 in the '''transfer amount input bar'''.
Click on '''Pour'''.

Keep '''Potassium chloride''' bottle aside.
||Drag the '''Potassium chloride''' bottle over to '''weighing boat 1'''.

Type 5 in the '''transfer amount input bar'''.
Click on '''Pour'''.

Keep '''Potassium chloride''' bottle aside.
|-
||Drag the '''weighing boat 1''' and place it on '''Flask 1'''.

In the '''transfer amount input bar''', Type 5. Click on '''pour'''.

Drag the '''weighing boat''' aside.
||Drag the '''weighing boat 1''' and place it on '''Flask 1'''.

In the '''transfer amount input bar''', Type 5.
Click on '''pour'''.

Keep the '''weighing boat''' aside.
|-
||In the '''Solution Info Panel''', click on '''Solid''' radio button.

Point to '''Species''' and '''grams''' columns.
||In the '''Solution Info Panel''', click on '''Solid''' radio button.

Observe, '''Species''' and '''grams''' columns.

Since all the '''potassium chloride''' is soluble in water, there is no solid '''Potassium chloride''' in the flask.

Hence it indicates zero grams.

This indicates that '''potassium chloride''' is readily soluble in water.
|-
||Place the '''weighing boat''' back on the '''Scale'''. Press '''TARE'''.

Type 15 in the '''transfer amount input bar'''. Click on '''pour'''.
||Let us keep on adding '''Potassium chloride''' to flask 1 until undissolved '''Potassium chloride''' remains in '''flask 1'''.

Place the '''weighing boat 1''' back on the '''Scale'''. Click on '''TARE'''.

Drag and place '''Potassium chloride''' bottle over '''weighing boat 1'''

Type 15 in the '''transfer amount input bar'''. Click on '''pour'''.

Keep '''Potassium chloride''' bottle aside.
|-
||'''Tools'''>>'''Transfer Bar'''>>'''Realistic Transfer'''.

Drag and place '''weighing boat 1''' over '''flask 1'''.

Click on '''Pour''' button gradually.
||Change the '''Transfer Bar''' to '''Realistic Transfer''' using '''Tools''' menu.

Drag and place '''weighing boat 1''' over '''flask 1'''.

Click on '''Pour''' button gradually.
|-
||Point to '''Solution info panel'''.
||Observe the '''Solution info panel'''.

Observe '''grams''' column, approximately 2 grams of '''Potassium chloride''' remains undissolved.
|-
||Cursor on '''Workbench'''.
||Let us now check if increase in temperature increases or decreases the solubility.
|-
||Click on Select tool icon, choose Bunsen Burner.

Bring the '''Bunsen Burner''' close to '''flask 1'''.
||Click on '''Select tool''' icon, choose '''Bunsen Burner'''.

Bring the '''Bunsen Burner''' close to '''flask 1'''.
|-
||Place '''flask 1''' over '''Bunsen Burner'''.
||Place '''flask 1''' over '''Bunsen Burner'''.

The flask gets heated quickly and undissolved '''potassium chloride''' dissolves completely.
|-
||Point to '''Solution info panel'''.
||Observe the temperature, as temperature increases '''potassium chloride''' dissolves.

At approximately 40oC, '''potassium chloride''' dissolves completely.

Note that '''grams''' column shows zero value.
|-
||Click on the '''Burner'''.

Two black arrows pointing up and down appear.

Click on the down pointing arrow to turn off the burner.
||We can turn off the flame of the '''Bunsen Burner''' when not required.

Click on the '''Burner'''. Two black arrows pointing up and down appear.

Click on the down pointing arrow to turn off the '''Burner'''.
|-
||Cursor on the '''workbench'''.
||Now I will demonstrate the solubility of '''Cerium(III) Sulphate'''.
|-
||'''Slide Number 5'''

'''Solubility'''
||Note that solubility of '''Cerium(III) Sulphate''' is much lower than '''potassium chloride'''.
|-
||Drag the '''distilled water''' tank over to '''graduated cylinder'''.

In the '''transfer amount input bar''', Type 50. Click on '''pour'''.

Keep the '''distilled water''' aside.
||Transfer 50 mL of '''Distilled water''' to '''graduated cylinder''' using '''Precise transfer'''.

Keep the '''Distilled water''' aside.
|-
||In the '''transfer amount input bar''', Type 50. Click on '''pour'''.

Keep the '''graduated cylinder''' aside.
||Now transfer 50 mL of '''Distilled waterv to '''flask 2''' using '''Precise transfer'''.

Keep the '''graduated cylinder''' aside.
|-
||Drag the '''Weighing boat 2''' and place it on the '''Scale'''.

Click on '''TARE'''.

'''Tools'''>> Transfer Bar'''>> '''Precise Transfer'''.
||Drag '''Weighing boat 2''' and place it on the '''Scale'''.

Click on '''TARE'''.
|-
||Drag the '''Cerium(III) Sulphate''' bottle over to '''Weighing boat 2'''.

Type 1 in the '''transfer amount input bar'''.
Click on '''Pour'''.

Keep '''Cerium(III)Sulphate''' bottle aside.
||We will begin by dissolving just 1 g of '''Cerium(III) Sulphate'''.

Transfer 1 g of '''Cerium(III) Sulphate''' to '''Weighing boat 2'''.

Keep '''Cerium(III) Sulphate''' bottle aside.
|-
||Drag the Weighing boat 2 and place it on Flask 2.

In the transfer amount input bar, type 1.

Click on Pour.

Keep the Weighing boat aside.
||Transfer 1 g of '''Cerium(III) Sulphate''' from '''Weighing boat 2''' to '''Flask 2'''.

Keep the '''Weighing boat''' aside.
|-
||Point to '''Solution info panel'''.

||In the '''Solution info panel''', observe '''Species''' and '''grams''' columns.

Since all the Cerium(III) Sulphate''' is soluble in water, it indicates zero grams.
|-
||Place the '''Weighing boat 2''' on '''Scale'''. Press '''TARE'''.

Type 5 in the '''transfer amount input bar'''.

Click on '''Pour'''.
||Let us add more '''Cerium(III) Sulphate''' to '''flask 2''' to check the solubility.

Place the '''Weighing boat 2''' back on the '''Scale'''. Press '''TARE'''.

Weigh 5 grams of '''Cerium(III) Sulphate'''.
|-
||'''Tools'''>> Transfer Bar'''>> '''Realistic Transfer'''.

Point to '''Solution info panel'''.

Drag and place '''Weighing boat 2''' over '''flask 2'''.

Click on '''Pour''' button gradually.
||Change the '''transfer bar''' to '''Realistic Transfer'''.

Drag and place '''Weighing boat 2''' over '''flask 2'''.

Click on '''Pour''' button gradually.

Keep the '''Weighing boat 2''' aside.
|-
||Observe the '''Solution info panel'''.
||Observe the '''Solution info panel'''.

Observe '''grams''' column, approximately 3 grams of '''Cerium(III) Sulphate''' remains undissolved.
|-
||Cursor on the '''Workbench'''.
||Let us now check if increase in temperature increases or decreases the solubility.
|-
||Place the '''Bunsen Burner''' close to '''flask 2'''.

Click on the up pointing arrow at the side of the '''Burner'''.

Place flask 2 over '''Bunsen Burner'''.
||Bring the '''Bunsen Burner''' close to '''flask 2'''.

Click on the up pointing arrow to turn-on the '''burner'''.

Place flask 2 over '''Bunsen Burner'''.
|-
||Point to '''Solution info panel'''.
||Observe that '''grams''' column shows increase in value.

As the temperature increases, solubility of '''Cerium(III)Sulphate''' decreases.
|-
||Click on the down pointing arrow at the side of the '''Burner'''.
||Turn-off the '''Burner'''.
|-
||'''Slide Number 6'''

'''Results'''
||For '''potassium chloride''', solubility increases with increase in temperature.

For '''Cerium(III)Sulphate''', solubility decreases with increase in temperature.
|-
||Click on '''Problem description''' window.
||Click on '''Problem description''' window.

We need to check if dissolution of '''potassium chloride''' and '''Cerium (III) Sulphate''' is endothermic or exothermic.
|-
||Click on '''Workbench'''.
||Click on '''Workbench'''.
|-
||Click on the flask and press '''Delete''' on the keyboard.
||Let us delete '''Erlenmeyer Flasks''' from the '''workbench'''.

Click on the flask and press '''Delete''' on the keyboard.
|-
||Click on '''glassware''' icon.
Select '''Foam Cup'''.

Right-click, select '''Duplicate''' option from the '''context menu'''.
||Click on '''glassware''' icon.

Select '''Foam Cup'''.

We need two copies of '''Foam Cups'''.

Use '''Duplicate''' option from the '''Context menu'''.
|-
||Right-click, select '''Rename''' option from the '''context menu'''.
||Rename '''Foam Cups''' as 1 and 2.
|-
||Drag the '''distilled water''' tank over to '''graduated cylinder'''.

In the '''transfer amount input bar''', type 50. Click on '''Pour'''.

Keep the '''distilled water''' aside.
||Change the '''Transfer Bar''' to '''Precise Transfer'''.

Transfer 50 mL of '''Distilled water''' to '''graduated cylinder''' using '''Precise transfer'''.

Keep the '''Distilled water''' aside.
|-
||Drag '''Foam cup 1''' and keep at the center of the table.

Drag and place the '''graduated cylinder''' over '''Foam cup 1'''.

In the '''transfer amount input bar''', Type 50. Click on '''Pour'''.

Keep the '''graduated cylinder''' aside.
||Place '''Foam cups''' at a convenient location on the '''workbench'''.

Transfer 50 mL of '''Distilled water''' to '''Foam cup 1''' using '''Precise transfer'''.

Keep the '''graduated cylinder''' aside.
|-
||Click on '''Foam cup 1'''.

Point to temperature.
||Click on '''Foam cup 1'''.

In the '''Solution info panel''', observe the temperature on the thermometer.

It shows 25o C.
|-
||'''Slide Number 7'''

'''Foam cup''' acts as '''Calorimeter''' for measurements made at constant pressure.

Heat exchange does not happen easily as it is a better insulator than glass.
||'''Foam cup acts as '''Calorimeter''' for measurements made at constant pressure.

Heat exchange does not happen easily as it is a better insulator than glass.
|-
||Place the '''weighing boat 1''' on the scale. Press '''TARE'''.

Drag the '''potassium chloride''' bottle over to '''weighing boat'''.

Type 5 in the '''transfer amount input bar'''.
Click on '''pour'''.

Keep '''potassium chloride''' bottle aside.
||Place the '''weighing boat 1''' on the '''Scale'''. Press '''TARE'''.

Weigh 5 grams of '''potassium chloride'''.

Keep '''potassium chloride''' bottle aside.
|-
||Bring '''weighing boat 1''' over to '''Foam cup 1'''.

Type 5 in the '''transfer amount input bar'''.

Click on '''pour'''.
||Bring '''weighing boat 1''' over to '''Foam cup 1'''.

Type 5 in the '''transfer amount input bar'''.

Click on '''pour'''.
|-
||Click on '''Foam cup 1'''.

Point to temperature on '''Solution info panel'''.
||Again click on '''Foam cup 1'''.

Observe the temperature, it is now 21o C.

Dissolution of '''potassium chloride''' in water absorbs heat, hence temperature decreases.

It is an endothermic process.
|-
||Cursor on '''Workbench'''.
||Now let us repeat the same procedure for '''Cerium(III) Sulphate'''.
|-
|| Drag and place the '''graduated cylinder''' over '''Foam cup 2'''.

In the '''transfer amount input bar''', Type 50. Click on '''pour'''.

Keep the '''graduated cylinder''' aside.
||Fill the '''graduated cylinder''' with 50 mL '''Distilled water'''.

Transfer 50 mL of water from '''graduated cylinder''' to '''Foam cup 2'''.
|-
||Click on '''Foam cup 2'''.

Point to temperature on '''Solution info panel'''.
||Click on '''Foam cup 2'''.

Note the temperature of water, it shows 25o C.
|-
||Drag '''Cerium(III)Sulphate''' bottle over to '''weighing boat 2'''.

Type 2 in the '''transfer amount input bar'''.

Click on '''pour'''.
||Place '''weighing boat 2''' on the '''Scale'''. Press '''TARE'''.

Weigh 2 grams of '''Cerium(III) Sulphate'''.

Keep '''Cerium(III) Sulphate''' bottle aside.
|-
||Bring Weighing boat 2 over to Foam cup 2.

Type 2 in the '''transfer amount input bar'''.
Click on '''Pour'''.

Keep the '''Weighing boat''' aside.
||Drag '''Weighing boat 2''' over to '''Foam cup 2'''.

Type 2 in the '''transfer amount input bar'''.

Click on '''Pour'''.

Keep the '''Weighing boat''' aside.
|-
||Click on '''Foam cup 2'''.

Point to temperature on '''Solution info panel'''.
||Again Click on '''Foam cup 2'''.

Observe the temperature, it is now 27.54o C.

Dissolution of '''Cerium(III) Sulphate''' in water releases heat, hence temperature increases.

It is an exothermic process.
|-
||'''Slide Number 6'''

'''Results'''
{| style="border-spacing:0;width:14.499cm;"
|-
| style="border-top:0.05pt solid #000000;border-bottom:0.05pt solid #000000;border-left:0.05pt solid #000000;border-right:none;padding:0.097cm;" | '''Salt'''
| style="border-top:0.05pt solid #000000;border-bottom:0.05pt solid #000000;border-left:0.05pt solid #000000;border-right:none;padding:0.097cm;" | '''Initial Temp '''
| style="border-top:0.05pt solid #000000;border-bottom:0.05pt solid #000000;border-left:0.05pt solid #000000;border-right:none;padding:0.097cm;" | '''Temp after dissolution'''
| style="border-top:0.05pt solid #000000;border-bottom:0.05pt solid #000000;border-left:0.05pt solid #000000;border-right:none;padding:0.097cm;" | '''Reaction'''
| style="border:0.05pt solid #000000;padding:0.097cm;" | '''Solubility with increase in Temp'''
|-
| style="border-top:none;border-bottom:0.05pt solid #000000;border-left:0.05pt solid #000000;border-right:none;padding:0.097cm;" | '''KCl (5 g)'''
| style="border-top:none;border-bottom:0.05pt solid #000000;border-left:0.05pt solid #000000;border-right:none;padding:0.097cm;" | '''25o C'''
| style="border-top:none;border-bottom:0.05pt solid #000000;border-left:0.05pt solid #000000;border-right:none;padding:0.097cm;" | '''21o C'''
| style="border-top:none;border-bottom:0.05pt solid #000000;border-left:0.05pt solid #000000;border-right:none;padding:0.097cm;" | '''Endothermic '''
| style="border-top:none;border-bottom:0.05pt solid #000000;border-left:0.05pt solid #000000;border-right:0.05pt solid #000000;padding:0.097cm;" | '''Increases'''
|-
| style="border-top:none;border-bottom:0.05pt solid #000000;border-left:0.05pt solid #000000;border-right:none;padding:0.097cm;" | '''Ce2(SO4)3 (2 g)'''
| style="border-top:none;border-bottom:0.05pt solid #000000;border-left:0.05pt solid #000000;border-right:none;padding:0.097cm;" | '''25o C'''
| style="border-top:none;border-bottom:0.05pt solid #000000;border-left:0.05pt solid #000000;border-right:none;padding:0.097cm;" | '''27o C'''
| style="border-top:none;border-bottom:0.05pt solid #000000;border-left:0.05pt solid #000000;border-right:none;padding:0.097cm;" | '''Exothermic'''
| style="border-top:none;border-bottom:0.05pt solid #000000;border-left:0.05pt solid #000000;border-right:0.05pt solid #000000;padding:0.097cm;" | '''decreases'''
|-
|}

||Let us now analyse the results.

We observed that:
* For an endothermic process, solubility increases as temperature increases.
* For an exothermic process, solubility decreases as temperature increases.

These observations follow '''Le Chatelier's principle'''.
|-
||'''Slide Number 7'''

'''Summary'''
||Let us summarize.

In this tutorial we have,

Determined the solubilities of potassium Chloride and Cerium(III)sulphate with increase in temperature.

Observed that solubility of, potassium chloride is Endothermic and

Solubility of Cerium(III)Sulphate is exothermic.
|-
||'''Slide Number 8'''

'''Assignment 1'''
||As an assignment,

List some examples of exothermic and endothermic processes in your daily lives.

Explain why heat is absorbed or evolved during a reaction.
|-
||'''Slide Number 9'''

'''Assignment 2'''
||Determine whether dissolution of '''Sodium Chloride''' is exothermic or endothermic.

(Hint: The problems are under '''Solubility''' topic in '''load homework''' window)
|-
||'''Slide Number 10''':

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

Please download and watch it.
|-
||'''Slide Number 11''':

Spoken Tutorial workshops
||The Spoken Tutorial Project team:
* conducts workshops using spoken tutorials and
* gives certificates on passing online tests.

For more details, please write to us.
|-
||'''Slide Number 12''':

'''Forum for specific questions''':

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

Someone from our team will answer them
||Please post your timed queries in this forum.
|-
||'''Slide Number 17''':

'''Acknowledgement'''
||Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India.

More information on this mission is available at this link.
|-
||
||This tutorial is contributed by Snehalatha kaliappan and Madhuri Ganapathi from IIT Bombay.

Thank you for joining.
|-
|}

@@ Line 247: / Line 247: @@
 Click on the down pointing arrow to turn off the '''Burner'''.
 |-
 ||'''Slide Number 5'''
 '''Solubility'''
-||Note that solubility of '''Cerium(III) Sulphate''' is much lower than '''potassium chloride'''.
+||Now I will demonstrate the solubility of '''Cerium(III) Sulphate'''.
 |-
 ||Drag the '''distilled water''' tank over to '''graduated cylinder'''.

@@ Line 532: / Line 532: @@
 It is an exothermic process.
 |-
-||'''Slide Number 6'''
+||'''Slide Number 8'''
 '''Results'''
@@ Line 566: / Line 566: @@
 These observations follow  '''Le Chatelier's principle'''.
 |-
-||'''Slide Number 7'''
+||'''Slide Number 9'''
 '''Summary'''
@@ Line 579: / Line 579: @@
 Solubility of Cerium(III)Sulphate is exothermic.
 |-
-||'''Slide Number 8'''
+||'''Slide Number 10'''
 '''Assignment 1'''
@@ Line 588: / Line 588: @@
 Explain why heat is absorbed or evolved during a reaction.
 |-
-||'''Slide Number 9'''
+||'''Slide Number 11'''
 '''Assignment 2'''
@@ Line 595: / Line 595: @@
 (Hint: The problems are under '''Solubility''' topic in '''load homework''' window)
 |-
-||'''Slide Number 10''':
+||'''Slide Number 12''':
 '''About Spoken Tutorial project'''
@@ Line 602: / Line 602: @@
 Please download and watch it.
 |-
-||'''Slide Number 11''':
+||'''Slide Number 13''':
 Spoken Tutorial workshops
@@ Line 611: / Line 611: @@
 For more details, please write to us.
 |-
-||'''Slide Number 12''':
+||'''Slide Number 14''':
 '''Forum for specific questions''':
@@ Line 626: / Line 626: @@
 ||Please post your timed queries in this forum.
 |-
-||'''Slide Number 17''':
+||'''Slide Number 15''':
 '''Acknowledgement'''

@@ Line 334: / Line 334: @@
 Click on '''Pour''' button gradually.
-Keep the  '''Weighing boat 2''' aside.
 |-
 ||Observe the '''Solution info panel'''.
@@ Line 351: / Line 351: @@
 ||Bring the '''Bunsen Burner''' close to '''flask 2'''.
-Click on the up pointing arrow to turn-on the '''burner'''.
 Place flask 2 over '''Bunsen Burner'''.
 |-
 ||Point to '''Solution info panel'''.

@@ Line 69: / Line 69: @@
 In the First section: Check solubilities of '''Potassium chloride''' and '''Cerium(III)sulphate''' with temperature.
-In the Second section: Observe whether dissolution of '''Potassium chloride''' and '''Cerium sulphate''' is exothermic or endothermic.
+In Second section: Observe whether dissolution of '''Potassium chloride''' and '''Cerium sulphate''' is exothermic or endothermic.
 In the Third section: we have to explain the observations in section 1 and 2 based on a chemical principle.
@@ Line 218: / Line 218: @@
 ||Let us now check if increase in temperature increases or decreases the solubility.
 |-
-||Click on Select tool icon, choose Bunsen Burner.
+||Click on Select tool icon, choose '''Bunsen Burner'''.
 Bring the '''Bunsen Burner''' close to '''flask 1'''.
@@ Line 233: / Line 233: @@
 ||Observe the temperature, as temperature increases '''potassium chloride''' dissolves.
-At approximately 40<sup>o</sup>C, '''potassium chloride''' dissolves completely.
+At approximately 40<sup>o</sup> C, '''potassium chloride''' dissolves completely.
 Note that '''grams''' column shows zero value.
@@ Line 248: / Line 248: @@
 Click on the down pointing arrow to turn off the '''Burner'''.
 |-
-||Cursor on the '''workbench'''.
+||Slide
 ||Now I will demonstrate the solubility of '''Cerium(III) Sulphate'''.
 |-
@@ Line 268: / Line 268: @@
 Keep the '''graduated cylinder''' aside.
-||Now transfer 50 mL of '''Distilled waterv to '''flask 2''' using '''Precise transfer'''.
+||Now transfer 50 mL of '''Distilled water''' to '''flask 2''' using '''Precise transfer'''.
 Keep the '''graduated cylinder''' aside.
@@ Line 306: / Line 306: @@
 ||Point to '''Solution info panel'''.
-||In the '''Solution info panel''', observe '''Species''' and '''grams''' columns.
+||In the '''Solution Info panel''', observe '''Species''' and '''grams''' columns.
 Since all the Cerium(III) Sulphate''' is soluble in water, it indicates zero grams.
@@ Line 420: / Line 420: @@
 Transfer 50 mL of '''Distilled water''' to '''Foam cup 1''' using '''Precise transfer'''.
 |-
 ||Click on '''Foam cup 1'''.
@@ Line 436: / Line 435: @@
 Heat exchange does not happen easily as it is a better insulator than glass.
-||'''Foam cup acts as '''Calorimeter''' for measurements made at constant pressure.
+||'''Foam cups act as '''Calorimeter''' for measurements made at constant pressure.
 Heat exchange does not happen easily as it is a better insulator than glass.