ChemCollective-Virtual-Labs/C3/Determination-of-Equilibrium-constant/English - Revision history

PoojaMoolya at 10:29, 28 October 2020

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Madhurig at 11:38, 28 December 2017

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Madhurig at 11:35, 28 December 2017

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Madhurig at 11:18, 28 December 2017

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Madhurig at 07:33, 28 December 2017

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Madhurig: Created page with "{| border=1 || '''Time''' || '''Narration''' |- || '''Slide Number 1''' '''Title Slide''' || Welcome to this tutorial on '''Determination of Equilibrium Constant''' usi..."

2017-12-13T11:27:35Z

Created page with "{| border=1 || '''Time''' || '''Narration''' |- || '''Slide Number 1''' '''Title Slide''' || Welcome to this tutorial on '''Determination of Equilibrium Constant''' usi..."

New page

{| border=1
|| '''Time'''
|| '''Narration'''
|-
|| '''Slide Number 1'''

'''Title Slide'''
|| Welcome to this tutorial on '''Determination of Equilibrium Constant''' using '''Vlabs'''.
|-
|| '''Slide Number 2'''

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

To determine equilibrium constant for Cobalt chloride reaction.

Observe the effect of change in temperature and concentration on equilibrium.
|-
|| '''Slide Number 3'''

'''Pre-requisites'''

[http://www.spoken-tutorial.org/ 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 virtual labs''' version 2.1.03

Java version 8.
|-
||Double click on '''Vlabs icon'''.
|| Here I have opened '''Vlabs''' interface.

|-
|| Click on '''File''' menu, Scroll down to '''Load Homework''' option.

Point to the dialogue box.
|| Click on '''File''' menu.

Scroll down to '''Load Homework''' option.

'''Default Lab Setup''' dialogue-box opens.
|-
|| Click on '''Chemical Equilibrium'''.

Click on '''Cobalt Lab'''.
|| From the list, double-click on '''Chemical Equilibrium'''.

Two options appear.

Double-click on '''Cobalt Lab''' option.
|-
|| Point to '''Stockroom '''
|| '''Stockroom Explorer''' has required solutions and '''Problem Description'''.
|-
|| Click on '''Problem Description'''.

Point to the Assignments in the problem.
|| Double-click on '''Problem Description'''.

Problem description states that,

we need to apply '''Le Chatelier's principle''', for aqueous '''Cobalt chloride''' reaction.

Using the equilibrium concentration we need to find,

1. equilibrium constant for cobalt chloride reaction and

2. effect of temperature and reactant concentration on equilibrium.
|-
||
|| Let us define chemical equilibrium.
|-
|| '''Slide Number 5'''

'''Chemical Equilibrium'''
|| '''Chemical equilibrium''' is a state of the reversible reaction when two opposing reactions occur at the same rate.

Concentration of reactants and products do not change with time at equilibrium.

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

General Equilibrium Reaction

'''aA+ bB ⇌ cC+dD'''

'''Kc = [C]c x [D]d/[A]a x [B]b'''
|| This side shows a general Equilibrium Reaction.

This is the equation for Equilibrium Constant.
|-
|| '''Slide Number 7'''

'''Equilibrium Constant'''

'''[Co(H 2O)6]2+ + 4HCl + heat ⇌

'''CoCl4-2 + 6H2O'''

'''Kc= [ CoCl4-2]/[Co(H 2 O)6+2] x [Cl-]4'''
|| The chemical equation for this reaction is shown here.

Cobalt forms complexes with water molecules as well as chloride ions.

A solution of Hexaaquacobalt(II)complex is pink.

When hydrochloric acid is added to the solution, the color changes to blue.

This corresponds to the formation of Cobalt Chloride complex.

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

'''Factors Affecting Equilibrium Constant'''
|| Equilibrium Constant changes with,

1. Change in concentration of reactants or products and

2. Change in temperature.

|-
|| Click on '''Workbench'''.

Click on '''Cobalt chloride exp solutions''' cabinet on the '''Stockroom explorer'''.
|| '''Click on Workbench'''.

Double-click on '''Cobalt chloride experiment solutions''' cabinet.

|-
|| Double-Click on 1M '''Cobalt Chloride'''.

Point to the added flask.

Point to the colour in the flask.
|| Double-Click on '''1M Cobalt Chloride.'''

A flask with '''100 mL''' of '''1M Cobalt Chloride''' is added to the workbench.

Observe the colour of the solution in the flask.
|-
|| Point to '''Solution Info''' panel.

Point to the colour in the flask.
|| '''Solution Info''' panel shows the required information.

Color of the solution is pink due to presence of '''Hexaaquacobalt(II)complex'''.

Note the concentrations of '''Hexaaquacobalt(II)complex''', '''chloride ions''' and '''Cobalt chloride''' in your observation book.
|-
|| Double-Click on '''12 M HCl'''.
|| Double-Click on '''12 M HCl'''.
|-
|| Click on '''Glassware menu'''.

Click on '''Erlenmeyers'''.

From the list click on 250 mL flask.

Right-click on flask A.

From the context menu choose '''Rename''' option.

In the text box type '''A'''.

Click on '''OK''' button.
|| Click on '''Glassware '''menu.

Select '''Erlenmeyers'''.

From the list click on 250 mL '''Erlenmeyer''' flask.

Rename the flask as '''A'''.
|-
|| Click on '''Pipette'''. From the list click on 25 mL '''Pipette'''.

Click on 50 mL '''Buret''', click on '''Buret.'''
|| From the '''Glassware'''menu, select '''Pipets'''.

From the list, click on 25 mL '''Pipet'''.

From the '''Glassware''' menu, select 50 mL '''Buret'''.
|-
|| Bring the pipette over to 1M CoCl2 flask.

Select '''Precise transfer''' mode.

Type 25 in the Transfer Amount input bar.

Click on '''Withdraw'''.

Drag and keep the flask aside.
|| Using '''Pipet''', measure 25 mL of '''Cobalt chloride''' solution.

Click on '''Withdraw'''.

Keep the flask aside.
|-
|| Place the pipette over empty 250 ml '''Erlenmeyer''' flask.

Type 25 and Click on '''Pour'''.
|| Place the''' Pipet''' over '''flask A'''.

Type '''25''' and Click on '''Pour'''.

Keep the '''Pipet''' aside.

|-
|| Bring 12 M HCl flask on to 50 mL burette.

Type 50 in the transfer window. Click on '''Pour'''.
|| Fill the '''buret''' with 50 ml of '''12 M '''hydrochloric acid.

Bring '''12 M''' hydrochloric acid flask on to 50 mL '''buret'''.

Type 50 in the '''Transfer amount''' input bar.

Click on '''Pour.'''

Keep the flask aside.

|-
|| Bring the burette on to flask '''A'''.

Type 1 in the transfer bar and click on pour.
|| Bring the''' buret '''on to '''flask A'''.

Add hydrochloric acid from the '''burette''' in 1 ml increments, using '''Precise Transfer''' mode.

Type 1 in the '''Transfer amount''' input bar and click on '''Pour'''.
|-
|| Click on '''Pour''' button.
|| Similarly transfer another 6 ml of hydrochloric acid using '''Precise Transfer''' mode.

We have transferred 7 mL of hydrochloric acid to '''Flask A'''.

|-
|| Click on flask A.

Point to Solution Info Panel.
|| Notice the change in temperature on the thermometer.

Temperature decreases during the reaction.

It means that, the reaction is '''endothermic'''.
|-
|| Point to the solution info panel.
|| The total volume of solution in '''Flask A '''shows 32 mL.
|-
|| Point to Flask A.
|| Observe the color change in '''Flask A''', color changes to brown.
|-
|| Wait for few min till the numbers become constant.

Point to the solution info panel.
|| It may take a few seconds to reach equilibrium state.

Now the concentrations of the reactants and products are constant.

Note the values of the concentrations of '''Hexaaquacobalt(II)complex, '''
'''chloride ions ''' and '''cobalt chloride ''' in your observation book.

|-
|| Click on '''Pour'''.

Point to the solution info panel.
|| Continue the titration.

Pour 1 ml at a time into the flask.

Transfer another 8 ml of Hydrochloric acid to '''flask A'''.

Now we have transferred 15 ml of hydrochloric acid to '''flask A'''.

Total volume of liquid in '''flask A '''is 40 mL

Note the color change in '''Flask A.'''

Please wait for the reaction to reach equilibrium condition.
|-
|| Point to the concentrations in the Solution Info Panel.
|| Again note the concentrations of '''Hexaaquacobalt(II)complex''', '''chloride ions''' and '''cobalt chloride''' in your observation book.
|-
|| Click on Pour button 3 times to add 3mL of HCl

Point to Flask A.

Point to the concentrations in the Solution Info Panel.
|| Similarly add another 3 ml of hydrochloric acid to '''flask A'''.

Total volume in '''flask A''' is 43 mL.

Note the color change in '''flask A'''.

Note the concentrations in your observation book.

|-
|| Click on Pour button 5 times to add 5mL of HCl.

Point to Flask A.

Point to the concentrations in the Solution Info Panel.
|| Finally add 5 mL of hydrochloric acid''' from the''' buret'''.

Total volume in '''flask A''' is now 48 mL.

Note that we have added 23 mL of hydrochloric acid to '''flask A'''.

Color of the solution in '''flask A''' is blue.
|-
||
|| Again note the concentrations of '''Hexaaquacobalt(II)complex''', '''chloride ions''' and '''cobalt chloride''' at equilibrium in your observation book.
|-
|| Cursor on '''Vlabs''' window.
| | Let us see how to calculate '''Equilibrium Constant.'''
|-
|| '''Slide Number 9'''

'''Calulation of Equilibrium Constant Kc.'''

[CoCl4-2] <nowiki>= 0.208 mol/L</nowiki>

[Co(H2O)6+2] <nowiki>= </nowiki>0.574 mol/L

[Cl-] = 3.36 mol/L

Kc = [CoCl4-2] /[Co(H2O)6+2] [Cl-]4

'''Kc = 0.208/0.574 x (3.36)4 '''.

'''K c<nowiki>= </nowiki>2.84x10-3'''
|| Calculate '''Equilibrium Constant''' using the given formula.

Substitute the values of concentrations of '''cobalt chloride''', '''Hexaaquacobalt(II)complex''' and '''chloride ions''' in the equation.

This is the value of equilibrium constant after pouring 7 ml of '''hydrochloric acid'''.

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

'''Equilibrium Constant'''

Table of Kc values.

Point to Kc values.
|| Similarly, here are the values of equilibrium constant for 15, 18 and 23 mL of hydrochloric acid.

Since, temperature is constant, equilibrium constant(Kc ) values are almost the same.
|-
|| Cursor on '''workbench.'''
|| Switch to '''workbench.'''

Next I will demonstrate the effect of temperature on equilibrium.

Earlier we have observed that, this reaction is '''endothermic'''.

It means, heat is absorbed during the reaction.
|-
|| '''Slide Number 11'''

'''Le Chatelier's principle'''

|| '''Le Chatelier’s '''Principle states that,

If an equilibrium is disturbed by changing the conditions, position of equilibrium moves to counteract the change.

According to the principle, for endothermic reactions,

rate of forward reaction increases with increase in temperature.

|-
|| Drag and place the burette aside.
|| Back to the '''workbench'''.

Keep the burette aside.
|-
|| Right-click on flask A, from the context menu, select '''Thermal Properties'''.

In the input box, check the box for '''Insulated from surroundings'''.

Type 35 in the text box.
|| Let us increase the temperature of the reaction flask to '''350 C.'''

Right-click on flask '''A''', from the context menu, select '''Thermal Properties'''.

Input box opens.

In '''Set the temperature to''' text box, type '''35'''.

Check the box for '''Insulated from surroundings'''.

Click on '''OK'''.
|-
|| Point to thermometer.
|| Thermometer shows '''35 0 C.'''

|-
|| Point to '''Solution Info''' panel.
|| Note the values of concentrations of '''Hexaaquacobalt(II)complex''', '''Chloride ions''' and '''Cobalt Chloride'''.
|-
|| '''Slide Number 12'''

'''Effect of temperature on Kc'''

'''[CoCl4-2]<nowiki>= 0.447 </nowiki>mol/L''',

'''[Co(H2O)6+2] <nowiki>= 0.074 </nowiki>mol/L''',

'''[Cl-] <nowiki>= 5.00 </nowiki>mol/L'''

'''Kc<nowiki>=</nowiki>[CoCl4-2]/[Co(H2O)6+2] x [Cl-]4'''

'''Kc <nowiki>= </nowiki>0.447 /0.074 x (5.00)4'''

<nowiki>=</nowiki> 9.65x10-3

|| This is the calculated value of equilibrium constant at '''350 C'''.
|-
|| '''Kc at 350 C = 9.65x10-3

'''Kc at 250 C = 2.85x10-3'''
|| Compare it to equilibrium constant value with that at '''250 C'''.

Note that the value of '''Kc''' at '''350 C''' is greater than '''K0 value''' at '''250C'''.

This is because the reaction is an endothermic reaction.

As the temperature increases rate of forward reaction increases.

Hence more product is formed.
|-
|| '''Click on Workbench.'''

Right-click on pipette and''' '''buret, select '''Remove'''.
|| Switch to '''workbench''',

Remove the used '''pipet''' and '''Buret''' from the''' Workbench'''.
|-
|| Right-click on '''Flask A'''. Uncheck the box for '''Insulated from surroundings'''.
|| Right-click on flask '''A'''

From the context menu, select '''Thermal Properties'''.

Un-check the box for '''Insulated from surroundings'''.

Click '''OK'''.

This will bring the temperature back to 250C.

|-
|| Double-Click on '''6M Silver nitrate''' from Stockroom Explorer.

From the '''glassware''' menu, select 25 mL '''pipet'''.
|| Now let us remove the chloride ions from the reaction using '''Silver Nitrate'''.

Double-Click on '''6M Silver nitrate''' from '''Stockroom Explorer'''.

From the '''glassware''' menu, select 25 mL '''pipet'''.

|-
|| Click on ''' Withdraw'''

Type 5 in '''Transfer Amount input bar'''.

Click on Pour.
|| Withdraw 25 mL of '''AgNO3 ''' into the 25 mL '''Pipet'''.

Transfer 25 mL of '''AgNO3''' from '''pipet''' to '''flask A''' in 5 mL increments.

Type 5 in '''Transfer Amount input bar'''.

Click on Pour.
|-
|| Point to the thermometer.

Point to '''flask A'''

Point to the concentrations.

Click on '''Solid''' radio button.

Point to the '''grams''' column.

'''[CoCl4]2- <nowiki>= </nowiki>0.0554 mol/L'''

'''[Co(H2O)6]+2 = 0.3122 mol/L'''

'''[Cl-] = 2.808 mol/L'''

'''AgCl = 18.14 g'''
|| Note the temperature. It increase as you add silver nitrate to flask A.

Note the colour change.

It indicates the formation of '''Hexaaquacobalt(II)complex'''.

Click on '''Solid''' radio button.

Note the amount of '''AgCl''' in '''grams''' column.
|-
|| '''Slide Number 13'''

'''Chemical Equilibrium'''

'''Silver Nitrate Reaction'''

'''Cobalt chloride reaction'''
|| Silver nitrate('''AgNO3)''' reacts with chloride(Cl-) ions in solution to form silver chloride('''AgCl)'''.

Here chloride(Cl-) ions decrease in the solution, to compensate for the deficit,

Rate of reverse reaction increases.

Cobalt chloride complex decomposes to form '''HexaaquaCobalt(II) '''complex.

This example is a proof for '''LeChatelier's ''' principle.
|-
||
|| Let us summarize.

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

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

To determine equilibrium constant for Cobalt chloride reaction.

Observe the effect of change in temperature and concentration on equilibrium.
|-
|| '''Slide Number 15'''

'''Assignment'''

'''Cobalt chloride reaction'''
|| As an assignment,

Prepare a solution by adding 25 ml of Cobalt chloride solution and 23 ml of Hydrochloric acid.

Add 40 mL of water in 10 ml increments to the prepared solution

Observe the colour in the flask.

Calculate Equilibrium Constant before and after addition of water.

|-
|| '''Slide Number 16'''

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

Please download and watch it.
|-
|| '''Slide Number 17'''

'''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 18'''

'''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 on this forum.
|-
|| '''Slide Number 19'''

'''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 46: / Line 46: @@
 ||Click on '''File''' menu, Scroll down to '''Load Homework''' option.
-Point to the dialogue box.
+Point to the dialog box.
 ||Click on '''File''' menu.
 Scroll down to '''Load Homework''' option.
-'''Default Lab Setup''' dialogue-box opens.
+'''Default Lab Setup''' dialog-box opens.
 |-
 ||Click on '''Chemical Equilibrium'''.

@@ Line 38: / Line 38: @@
 '''ChemCollective virtual labs''' version 2.1.03
-Java version 8.
+'''Java''' version 8.
 |-
-||Double click on '''Vlabs icon'''.
+||Double click on '''Vlabs''' icon.
 ||Here I have opened '''Vlabs''' interface.

@@ Line 200: / Line 200: @@
 Click on 50 mL '''Buret''', click on '''Buret.'''
-|| From the '''Glassware'''menu, select '''Pipets'''.
+|| From the '''Glassware''' menu, select '''Pipets'''.
 From the list, click on 25 mL '''Pipet'''.
@@ Line 575: / Line 575: @@
 '''AgCl = 18.14 g'''
-|| Note the temperature. It increase as you add silver nitrate to flask A.
+|| Note the temperature. It increases as you add '''silver nitrate''' to flask A.
@@ Line 598: / Line 598: @@
 '''Cobalt chloride reaction'''
-|| Silver nitrate('''AgNO<sub>3</sub>)''' reacts with chloride(Cl<sup>-</sup>) ions in solution to form silver chloride('''AgCl)'''.
+|| '''Silver nitrate(AgNO<sub>3</sub>)''' reacts with '''chloride(Cl<sup>-</sup>) ions in solution to form '''silver chloride(AgCl)'''.

@@ Line 415: / Line 415: @@
 It means, heat is absorbed during the reaction.
 |-
-|| '''Slide Number 11'''
+|| '''Slide Number 11 & 12'''
 '''Le Chatelier's principle'''
@@ Line 463: / Line 463: @@
 || Note the values of concentrations of '''Hexaaquacobalt(II)complex''', '''Chloride ions''' and '''Cobalt Chloride'''.
 |-
-|| '''Slide Number 12'''
+|| '''Slide Number 13'''
 '''Effect of temperature on K<sub>c</sub>'''
@@ Line 486: / Line 486: @@
 || This is the calculated value of equilibrium constant at '''35<sup>0</sup> C'''.
 |-
-|| '''K<sub>c</sub> at 35<sup>0</sup> C = 9.65x10<sup>-3</sup>
+|| '''Slide Number 14'''
@@ Line 589: / Line 594: @@
 Note the amount of  '''silver chloride(AgCl)''' in '''grams''' column.
 |-
-|| '''Slide Number 13'''
+|| '''Slide Number 15'''
-'''Chemical Equilibrium'''
+'''Chemical Equilibrium: Equations'''
@@ Line 616: / Line 621: @@
 |-
-|| '''Slide Number 14'''
+|| '''Slide Number 16'''
 '''Summary'''
@@ Line 626: / Line 631: @@
 Observe the effect of change in temperature and concentration on equilibrium.
 |-
-|| '''Slide Number 15'''
+|| '''Slide Number 17 & 18'''
@@ Line 644: / Line 649: @@
 |-
-|| '''Slide Number 16'''
+|| '''Slide Number 19'''
 '''About Spoken Tutorial project'''
@@ Line 651: / Line 656: @@
 Please download and watch it.
 |-
-|| '''Slide Number 17'''
+|| '''Slide Number 20'''
 '''Spoken Tutorial workshops'''
@@ Line 663: / Line 668: @@
 |-
-|| '''Slide Number 18'''
+|| '''Slide Number 21'''
 '''Forum for specific questions:'''
@@ Line 678: / Line 683: @@
 || Please post your timed queries on this forum.
 |-
-|| '''Slide Number 19'''
+|| '''Slide Number 22'''
 '''Acknowledgement'''

@@ Line 143: / Line 143: @@
 Double-click on '''Cobalt chloride experiment  solutions''' cabinet on the '''Stockroom explorer'''.
-|| '''Click on Workbench'''.
+|| Click on '''Workbench'''.
 Double-click on '''Cobalt chloride experiment solutions''' cabinet.
@@ Line 258: / Line 258: @@
-Add hydrochloric acid from the '''burette''' in 1 ml increments, using '''Precise Transfer''' mode.
+Add hydrochloric acid from the '''burette''' in 1 mL increments, using '''Precise Transfer''' mode.
@@ Line 264: / Line 264: @@
 |-
 || Click on '''Pour''' button.
-|| Similarly transfer another 6 ml of hydrochloric acid using '''Precise Transfer''' mode.
+|| Similarly transfer another 6 mL of hydrochloric acid using '''Precise Transfer''' mode.
@@ Line 301: / Line 301: @@
 || Continue the titration.
-Pour 1 ml at a time into the flask.
+Pour 1 mL at a time into the flask.
-Transfer another 8 ml of Hydrochloric acid to '''flask A'''.
+Transfer another 8 mL of Hydrochloric acid to '''flask A'''.
-Now we have transferred 15 ml of hydrochloric acid to '''flask A'''.
+Now we have transferred 15 mL of hydrochloric acid to '''flask A'''.
@@ Line 321: / Line 321: @@
 || Again note the concentrations of '''Hexaaquacobalt(II)complex''', '''chloride ions''' and '''cobalt chloride''' in your observation book.
 |-
-|| Click on Pour button 3 times to add 3mL of HCl
+|| Click on '''Pour''' button 3 times to add 3mL of HCl
@@ Line 345: / Line 345: @@
 Point to the concentrations in the Solution Info Panel.
-|| Finally add 5 mL of hydrochloric acid''' from the''' buret'''.
+|| Finally add 5 mL of hydrochloric acid''' from the ''' buret'''.
@@ Line 360: / Line 360: @@
 |-
 || Cursor on '''Vlabs''' window.
-|| Let us see how to calculate '''Equilibrium Constant.'''
+|| Let us see how to calculate '''Equilibrium Constant'''.
 |-
 || '''Slide Number 9'''
@@ Line 430: / Line 430: @@
 |-
 || Drag and place the burette aside.
-|| Back to the '''workbench'''.
+|| Back to  '''workbench'''.
 Keep the burette aside.
@@ Line 509: / Line 509: @@
 || Switch to '''workbench''',
-Remove the used '''pipettee''' and '''burette''' from the''' Workbench'''.
+Remove the used '''pipette''' and '''burette''' from the''' Workbench'''.
 |-
 || Right-click on '''Flask A'''. Uncheck the box for '''Insulated from surroundings'''.
@@ Line 621: / Line 621: @@
 || In this tutorial, we have learnt,
-To determine equilibrium constant for Cobalt chloride reaction.
+To determine '''equilibrium constant''' for Cobalt chloride reaction.
@@ Line 634: / Line 634: @@
 '''Cobalt chloride reaction'''
 || As an assignment,
 Prepare a solution by adding 25 mL of Cobalt chloride solution and 23 mL of Hydrochloric acid.
 Add 40 mL of water in 10 mL increments to the prepared solution
 Observe the colour in the flask.
 Calculate Equilibrium Constant before and after addition of water.

@@ Line 22: / Line 22: @@
 [http://www.spoken-tutorial.org/ www.spoken-tutorial.org]
-|| To follow this tutorial, you should be familiar with
+|| To follow this tutorial, you should be familiar with,
-'''Chemcollective Vlabs interface'''.
+'''ChemCollective Vlabs interface'''.
 If not for relevant tutorials please visit our website.
@@ Line 36: / Line 36: @@
 '''Mac OS''' version 10.10.5
-'''Chemcollective virtual labs''' version 2.1.03
+'''ChemCollective virtual labs''' version 2.1.03
 Java version 8.
@@ Line 89: / Line 89: @@
 || '''Chemical equilibrium''' is a state of the reversible reaction when two opposing reactions occur at the same rate.
-Concentration of reactants and products do not change with time at equilibrium.
+Concentration of the reactants and products do not change with time at equilibrium.
 |-
@@ Line 99: / Line 99: @@
 '''K<sub>c</sub> = [C]<sup>c</sup> x [D]<sup>d</sup>/[A]<sup>a</sup> x [B]<sup>b</sup>'''
-|| This side shows a general Equilibrium Reaction.
+|| This side shows a general '''Equilibrium Reaction'''.
-This is the equation for Equilibrium Constant.
+This is the equation for '''Equilibrium Constant'''.
 |-
 || '''Slide Number 7'''
@@ Line 120: / Line 120: @@
-A solution of Hexaaquacobalt(II)complex is pink.
+A solution of '''Hexaaquacobalt(II)complex''' is pink.
-When hydrochloric acid is added to the solution, the color changes to blue.
+When hydrochloric acid is added to the solution, the colour changes to blue.
-This corresponds to the formation of Cobalt Chloride complex.
+This corresponds to the formation of '''Cobalt Chloride complex'''.
 |-
@@ Line 168: / Line 168: @@
 || '''Solution Info''' panel shows the required information.
-Color of the solution is pink due to presence of '''Hexaaquacobalt(II)complex'''.
+Colour of the solution is pink due to presence of '''Hexaaquacobalt(II)complex'''.
 Note the concentrations of '''Hexaaquacobalt(II)complex''', '''chloride ions''' and '''Cobalt chloride'''  in your observation book.
@@ Line 177: / Line 177: @@
 || Click on '''Glassware menu'''.
-Click on '''Erlenmeyers'''.
+Select '''Erlenmeyers'''.
-From the list click on 250 mL flask.
+From the list click on '''250 mL Erlenmeyer Flask'''.
@@ Line 226: / Line 226: @@
 |-
 || Place the pipette over empty 250 ml '''Erlenmeyer''' flask.
 Type 25 and Click on '''Pour'''.
 || Place the''' Pipet''' over '''flask A'''.
 Type '''25''' and Click on '''Pour'''.
 Keep the '''Pipet''' aside.
 |-
 || Bring 12 M HCl flask on to 50 mL burette.
 Type 50 in the transfer window. Click on '''Pour'''.
-|| Fill the '''buret''' with 50 ml of '''12 M '''hydrochloric acid.
+|| Fill the '''buret''' with 50 ml of '''12 M hydrochloric acid'''.
-Bring '''12 M''' hydrochloric acid flask on to 50 mL '''buret'''.
+Bring '''12 M hydrochloric acid'''  flask on to 50 mL '''buret'''.
@@ Line 250: / Line 246: @@
-Click on '''Pour.'''
+Click on '''Pour'''.
@@ Line 259: / Line 255: @@
 Type 1 in the transfer bar and click on pour.
-|| Bring the''' buret '''on to '''flask A'''.
+|| Bring the '''buret''' on to '''flask A'''.
@@ Line 284: / Line 280: @@
 |-
 || Point to the solution info panel.
-|| The total volume of solution in '''Flask A '''shows 32 mL.
+|| The total volume of solution in '''Flask A''' shows 32 mL.
 |-
 || Point to Flask A.
-|| Observe the color change in '''Flask A''', color changes to brown.
+|| Observe the colour change in '''Flask A''', colour changes to brown.
 |-
 || Wait for few min till the numbers become constant.
@@ Line 296: / Line 292: @@
 Now the concentrations of the reactants and products are constant.
-Note the values of the concentrations of '''Hexaaquacobalt(II)complex, '''
+Note the values of the concentrations of '''Hexaaquacobalt(II)complex''',
 '''chloride ions ''' and '''cobalt chloride '''  in your observation book.