BITSAT SERIES
Chemistry

Law Of Chemical Equilibrium And Equilibrium Constant

12 previous year questions.

Volume: 12 Ques
Yield: Medium

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2025
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2022
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Chapter Questions
12 MCQs

01
PYQ 2012
medium
chemistry ID: bitsat-2
The reaction, , is exothermic and reversible. A mixture of , , and is at equilibrium in a closed container. Now a certain quantity of extra is introduced into the container, the volume remaining the same. Which of the following is/are true?
1
The pressure inside the container will not change.
2
The temperature will not change.
3
The temperature will increase.
4
The temperature will decrease.
02
PYQ 2013
medium
chemistry ID: bitsat-2
If 1.0 mole of is introduced into a 1.0 litre flask at 1000 K, at equilibrium ( ), which one is correct?
1

2

3

4

03
PYQ 2013
hard
chemistry ID: bitsat-2
For the reaction , is
1

2

3

4

04
PYQ 2015
medium
chemistry ID: bitsat-2
Which of the following according to Le-Chatelier’s principle is correct?
1
Increase in temperature favours the endothermic reaction
2
Increase in temperature favours the exothermic reaction
3
Increase in pressure shifts the equilibrium in that side in which number of gaseous moles increases
4
All of the above are true
05
PYQ 2016
medium
chemistry ID: bitsat-2
The degree of dissociation of PCl₅(g) obeying the equilibrium PCl₅ rightleftharpoons PCl₃ + Cl₂ is related to the equilibrium pressure by:
1

2

3

4
α ∝ P
06
PYQ 2018
medium
chemistry ID: bitsat-2
When N₂O₅ is heated at certain temperature, it dissociates as N₂O₅(g) rightleftharpoons N₂O₃(g) + O₂(g); K₁=2.5 At the same time N₂O₃(g) rightleftharpoons N₂O(g) + O₂(g) If initially 4.0 moles of N₂O₅ are taken in a 1.0L flask and equilibrium concentration of O₂ is 2.5M, equilibrium concentration of N₂O₅ is:
1

2

3

4
1.846M
07
PYQ 2019
medium
chemistry ID: bitsat-2
Which of the following according to Le-Chatelier’s principle is correct?
1
Increase in temperature favours the endothermic reaction
2
Increase in temperature favours the exothermic reaction
3
Increase in pressure shifts the equilibrium in that side in which number of gaseous moles increases
4
All of the above are true
08
PYQ 2020
medium
chemistry ID: bitsat-2
The degree of dissociation of PCl₅(g) obeying the equilibrium PCl₅ rightleftharpoons PCl₃ + Cl₂ is related to the equilibrium pressure P by:
1

2

3

4
α ∝ P
09
PYQ 2022
medium
chemistry ID: bitsat-2
For an isomerization reaction , the temperature dependence of the equilibrium constant is given by: {The value of at Hook is, therefore:}
1

2

3

4

10
PYQ 2022
medium
chemistry ID: bitsat-2
Standard entropy of , , and are 60, 40, and 50 J K mol , respectively. For the reaction, $ \Delta H = -30 \, \text{kJ}$, to be at equilibrium, the temperature will be:
1
1250 K
2
500 K
3
750 K
4
1000 K
11
PYQ 2025
medium
chemistry ID: bitsat-2
For the reaction , if initially 1 mole of and 3 moles of are taken and at equilibrium 0.4 moles of are formed, find the equilibrium concentration of .
1
2.4 moles
2
2.8 moles
3
3.4 moles
4
3.0 moles
12
PYQ 2025
medium
chemistry ID: bitsat-2
For the reaction , the equilibrium constant is 0.5 at a certain temperature. If initially, 1 mole of and 3 moles of are placed in a 1 L container, what is the equilibrium concentration of ?
1
0.6
2
0.3
3
0.10
4
0.9