50+ JEE Mains MCQ Questions Equilibrium with Solutions

Preparing for the Joint Entrance Exam (JEE) can be a daunting task. With so many subjects to cover and so many topics to study, it can be challenging to know where to start. One essential topic in the JEE Mains syllabus is the Equilibrium. In this article, we will provide 50+ MCQ questions on the Equilibrium, along with detailed solutions to help you prepare for the JEE Mains exam.

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These 50+ MCQ questions are selected by the experts of studyrate.in and these are more difficult questions, which will help you to better understand Equilibrium JEE Mains MCQ Questions with Answers.

Equilibrium JEE Mains MCQ


In the equilibrium reaction N₂(g) + 3H₂(g) ⇌ 2NH₃(g), if the pressure is increased, what will be the effect on the equilibrium position?
A) Shift towards the reactants
B) Shift towards the products
C) No effect on the equilibrium position
D) Cannot be determined

Answer: B Explanation: According to Le Chatelier’s principle, if the pressure is increased, the equilibrium will shift in the direction that reduces the number of moles of gas. In this case, the equilibrium will shift towards the products side to decrease the total number of gas moles.

Which of the following statements is true regarding the equilibrium constant (K)?
A) It is dependent on the initial concentrations of reactants and products.
B) It is constant at all temperatures.
C) It represents the rate of the forward reaction.
D) It can be influenced by the addition of a catalyst.

Answer: B Explanation: The equilibrium constant (K) is a constant value at a given temperature and is independent of the initial concentrations. It represents the ratio of the concentrations of products to reactants at equilibrium.

For the equilibrium reaction A + B ⇌ C + D, if the concentration of reactant A is increased, what will be the effect on the equilibrium position?
A) Shift towards products
B) Shift towards reactants
C) No effect on the equilibrium position
D) Cannot be determined

Answer: B Explanation: According to Le Chatelier’s principle, if the concentration of reactant A is increased, the equilibrium will shift in the direction that consumes reactant A. In this case, the equilibrium will shift towards the reactants to consume the excess A and restore equilibrium.

The equilibrium constant (Kp) is related to the equilibrium constant (Kc) by:
A) Kp = Kc(RT)^(∆n)
B) Kp = Kc/RT
C) Kp = Kc(∆n)^(RT)
D) Kp = Kc^(RT)

Answer: A Explanation: The equilibrium constant (Kp) in terms of partial pressures is related to the equilibrium constant (Kc) in terms of concentrations by the equation Kp = Kc(RT)^(∆n), where ∆n is the difference in the number of moles of gaseous products and reactants.

The reaction quotient (Q) can be used to:
A) Determine the direction in which the reaction will proceed to reach equilibrium.
B) Calculate the rate constant of the reaction.
C) Determine the activation energy of the reaction.
D) Determine the equilibrium constant (K) of the reaction.

Answer: A Explanation: The reaction quotient (Q) can be used to determine the direction in which the reaction will proceed to reach equilibrium. By comparing Q with the equilibrium constant (K), one can determine if the reaction is at equilibrium or if it needs to shift in a particular direction to reach equilibrium.

Which of the following factors does not affect the equilibrium constant (K) for a reaction?
A) Temperature
B) Catalyst
C) Pressure
D) Addition or removal of reactants or products

Answer: D Explanation: The equilibrium constant (K) for a reaction is not affected by the addition or removal of reactants or products once the system has reached equilibrium. It is only influenced by changes in temperature.


The equilibrium constant (K) for the reaction N₂(g) + O₂(g) ⇌ 2NO(g) is 4.0 × 10^4 at a certain temperature. What will be the value of K for the reaction 2NO(g) ⇌ N₂(g) + O₂(g) at the same temperature?
A) 4.0 × 10^4
B) 2.0 × 10^4
C) 1.0 × 10^4
D) 8.0 × 10^4

Answer: B Explanation: For the reverse reaction, the equilibrium constant is the reciprocal of the forward reaction. Therefore, the value of K for the reaction 2NO(g) ⇌ N₂(g) + O₂(g) will be 1/(4.0 × 10^4) = 2.0 × 10^(-4).

A reaction has an equilibrium constant (K) value of 1.0 × 10^6. Which of the following statements is true regarding the reaction at equilibrium?
A) The reactants are completely consumed.
B) The products are completely consumed.
C) The concentration of reactants and products is equal.
D) The reaction is in dynamic equilibrium.

Answer: D Explanation: A reaction at equilibrium, indicated by a non-zero equilibrium constant, is in a state of dynamic equilibrium where the forward and reverse reactions occur at the same rate. The reactants and products are present in a constant ratio, but they are not completely consumed.

In the equilibrium reaction N₂O₄(g) ⇌ 2NO₂(g), if the volume of the container is decreased, what will be the effect on the equilibrium position?
A) Shift towards the reactants
B) Shift towards the products
C) No effect on the equilibrium position
D) Cannot be determined

Answer: B Explanation: According to Le Chatelier’s principle, if the volume of the container is decreased, the equilibrium will shift in the direction that reduces the total number of gas moles. In this case, the equilibrium will shift towards the products side to decrease the number of gas moles.

The equilibrium constant (K) for the reaction H₂(g) + I₂(g) ⇌ 2HI(g) is 50 at a certain temperature. If the initial concentrations of H₂, I₂, and HI are 0.1 M, 0.2 M, and 0.5 M, respectively, what is the value of Q (reaction quotient)?
A) 12.5
B) 50
C) 25
D) 6.25

Answer: C Explanation: The reaction quotient (Q) is calculated using the concentrations of the reactants and products at any given time. In this case, Q = [HI]^2 / ([Hâ‚‚] x [Iâ‚‚]) = (0.5)^2 / (0.1 x 0.2) = 25.

Which of the following factors affects the rate of a reaction at equilibrium?
A) Temperature
B) Catalyst
C) Pressure
D) Addition or removal of reactants or products

Answer: B Explanation: The rate of a reaction at equilibrium is not influenced by temperature, pressure, or the addition or removal of reactants or products. However, the presence of a catalyst can still affect the rate of the forward and reverse reactions, allowing equilibrium to be reached more quickly.

The equilibrium constant (K) for the reaction CO(g) + Cl₂(g) ⇌ COCl₂(g) is 100 at a certain temperature. If the concentration of CO is doubled while the concentrations of Cl₂ and COCl₂ remain unchanged, what will be the new value of K?
A) 200
B) 50
C) 100
D) 25

Answer: A Explanation: The equilibrium constant (K) is a constant at a given temperature. Doubling the concentration of CO will lead to a new equilibrium position, but the value of K remains the same.

The equilibrium constant (K) for the reaction A + B ⇌ C is 0.05. What will be the value of K for the reverse reaction C ⇌ A + B?
A) 0.05
B) 0.02
C) 20
D) 50

Answer: C Explanation: For the reverse reaction, the equilibrium constant is the reciprocal of the forward reaction. Therefore, the value of K for the reverse reaction C ⇌ A + B will be 1/0.05 = 20.

The equilibrium constant (K) for the reaction 2A + B ⇌ 3C is 4.0 × 10^3 at a certain temperature. If the concentration of B is doubled while the concentrations of A and C remain unchanged, what will be the new value of K?
A) 1.0 × 10^4
B) 2.0 × 10^3
C) 4.0 × 10^3
D) 2.0 × 10^4

Answer: C Explanation: For the reverse reaction, the equilibrium constant is the reciprocal of the forward reaction. Therefore, the value of K for the reverse reaction C ⇌ A + B will be 1/0.05 = 20.

The equilibrium constant (K) for the reaction N₂(g) + 3H₂(g) ⇌ 2NH₃(g) is 10^2 at a certain temperature. If the concentrations of N₂ and H₂ are both doubled while the concentration of NH₃ remains unchanged, what will be the new value of K?
A) 1.0 × 10^2
B) 2.0 × 10^2
C) 4.0 × 10^2
D) 8.0 × 10^2

Answer: D Explanation: Doubling the concentrations of Nâ‚‚ and Hâ‚‚ will lead to a new equilibrium position, but the value of K remains the same.

The equilibrium constant (K) for the reaction A + B ⇌ C is 0.01. If the concentrations of A and B are both halved while the concentration of C remains unchanged, what will be the new value of K?
A) 0.01
B) 0.02
C) 0.005
D) 0.001

Answer: C Explanation: Halving the concentrations of A and B will lead to a new equilibrium position, but the value of K remains the same.

In the equilibrium reaction N₂(g) + O₂(g) ⇌ 2NO(g), if the temperature is increased, what will be the effect on the equilibrium position?
A) Shift towards the reactants
B) Shift towards the products
C) No effect on the equilibrium position
D) Cannot be determined

Answer: B Explanation: According to Le Chatelier’s principle, if the temperature is increased, the equilibrium will shift in the direction that absorbs heat. In this case, the equilibrium will shift towards the products side to absorb the additional heat.

The equilibrium constant (K) for the reaction N₂(g) + 3H₂(g) ⇌ 2NH₃(g) is 2.0 × 10^(-3) at a certain temperature. If the concentration of NH₃ is increased by a factor of 10 while the concentrations of N₂ and H₂ remain unchanged, what will be the new value of K?
A) 2.0 × 10^(-4)
B) 2.0 × 10^(-2)
C) 2.0 × 10^(-1)
D) 2.0 × 10^3

Answer: B Explanation: Increasing the concentration of NH₃ will lead to a new equilibrium position, and the value of K will also change. The new value of K can be calculated by multiplying the original value of K by the concentration change factor, which is 10 in this case. Therefore, the new value of K is (2.0 × 10^(-3)) × 10 = 2.0 × 10^(-2).

The equilibrium constant (K) for the reaction A + B ⇌ C + D is 1.0 × 10^(-2). If the concentration of A is halved while the concentrations of B, C, and D remain unchanged, what will be the new value of K?
A) 1.0 × 10^(-2)
B) 2.0 × 10^(-2)
C) 5.0 × 10^(-3)
D) 2.0 × 10^(-3)

Answer: C Explanation: Halving the concentration of A will lead to a new equilibrium position, and the value of K will also change. The new value of K can be calculated by dividing the original value of K by the concentration change factor, which is 0.5 in this case. Therefore, the new value of K is (1.0 × 10^(-2)) / 0.5 = 2.0 × 10^(-2).

The equilibrium constant (K) for the reaction A + B ⇌ C + D is 0.1. If the concentrations of A and B are both doubled while the concentrations of C and D remain unchanged, what will be the new value of K?
A) 0.05
B) 0.2
C) 0.4
D) 0.8

Answer: C Explanation: Doubling the concentrations of A and B will lead to a new equilibrium position, and the value of K will also change. The new value of K can be calculated by multiplying the original value of K by the concentration change factor, which is 2 in this case. Therefore, the new value of K is (0.1) × 2 = 0.2.

The equilibrium constant (K) for the reaction A + B ⇌ C + D is 5.0 × 10^(-3). If the concentrations of C and D are both halved while the concentrations of A and B remain unchanged, what will be the new value of K?
A) 2.5 × 10^(-3)
B) 5.0 × 10^(-3)
C) 1.0 × 10^(-2)
D) 2.0 × 10^(-2)
.

Answer: A Explanation: Halving the concentrations of C and D will lead to a new equilibrium position, and the value of K will also change. The new value of K can be calculated by dividing the original value of K by the concentration change factor, which is 0.5 in this case. Therefore, the new value of K is (5.0 × 10^(-3)) / 0.5 = 2.5 × 10^(-3)

The equilibrium constant (K) for the reaction A ⇌ B + C is 0.2. If the concentrations of B and C are both doubled while the concentration of A remains unchanged, what will be the new value of K?
A) 0.2
B) 0.1
C) 0.4
D) 0.8

Answer: C Explanation: Doubling the concentrations of B and C will lead to a new equilibrium position, and the value of K will also change. The new value of K can be calculated by multiplying the original value of K by the concentration change factor, which is 2 in this case. Therefore, the new value of K is (0.2) × 2 = 0.4.

The equilibrium constant (K) for the reaction A ⇌ B + C is 0.01. If the concentrations of A, B, and C are all halved, what will be the new value of K?
A) 0.01
B) 0.02
C) 0.005
D) 0.001

Answer: A Explanation: Halving the concentrations of A, B, and C will lead to a new equilibrium position, but the value of K remains the same.

The equilibrium constant (K) for the reaction A ⇌ B + C is 0.02. If the concentration of A is tripled while the concentrations of B and C remain unchanged, what will be the new value of K?
A) 0.06
B) 0.02
C) 0.04
D) 0.01

Answer: A Explanation: Tripling the concentration of A will lead to a new equilibrium position, and the value of K will also change. The new value of K can be calculated by multiplying the original value of K by the concentration change factor, which is 3 in this case. Therefore, the new value of K is (0.02) × 3 = 0.06.


The equilibrium constant (K) for the reaction N₂O₄(g) ⇌ 2NO₂(g) is 0.02 at a certain temperature. If the pressure is increased by a factor of 4 while the concentrations remain unchanged, what will be the new value of K?
A) 0.08
B) 0.02
C) 0.01
D) 0.005

Answer: C Explanation: Increasing the pressure by a factor of 4 will lead to a new equilibrium position, but the value of K remains the same.

The equilibrium constant (K) for the reaction 2CO(g) + O₂(g) ⇌ 2CO₂(g) is 5.0 × 10^(-3) at a certain temperature. If the volume is decreased by a factor of 2 while the concentrations remain unchanged, what will be the new value of K?
A) 5.0 × 10^(-3)
B) 1.0 × 10^(-2)
C) 2.5 × 10^(-3)
D) 1.25 × 10^(-3)

Answer: B Explanation: Decreasing the volume by a factor of 2 will lead to a new equilibrium position, but the value of K remains the same.

The equilibrium constant (K) for the reaction 2H₂(g) + O₂(g) ⇌ 2H₂O(g) is 4.0 × 10^(-3) at a certain temperature. If the temperature is increased, what will be the effect on the equilibrium position?
A) Shift towards the reactants
B) Shift towards the products
C) No effect on the equilibrium position
D) Cannot be determined

Answer: A Explanation: According to Le Chatelier’s principle, if the temperature is increased, the equilibrium will shift in the direction that absorbs heat. In this case, the equilibrium will shift towards the reactants side to absorb the additional heat.

The equilibrium constant (K) for the reaction A + B ⇌ C is 0.1. If the concentration of A is quadrupled while the concentrations of B and C remain unchanged, what will be the new value of K?
A) 0.4
B) 0.1
C) 0.025
D) 0.025
.

Answer: A Explanation: Quadrupling the concentration of A will lead to a new equilibrium position, and the value of K will also change. The new value of K can be calculated by multiplying the original value of K by the concentration change factor, which is 4 in this case. Therefore, the new value of K is (0.1) × 4 = 0.4

The equilibrium constant (K) for the reaction A ⇌ B + C is 0.05. If the concentration of C is doubled while the concentrations of A and B remain unchanged, what will be the new value of K?
A) 0.05
B) 0.025
C) 0.1
D) 0.2

Answer: C Explanation: Doubling the concentration of C will lead to a new equilibrium position, and the value of K will also change. The new value of K can be calculated by multiplying the original value of K by the concentration change factor, which is 2 in this case. Therefore, the new value of K is (0.05) × 2 = 0.1.

We hope there JEE MCQ of Class 11 Equilibrium will help you to score an excellent rank in JEE Mains and Advanced. If you have any queries feel free to write in the comments section. We at Study Rate are always ready to serve our students.

Sneha

Master's in Biology, Skilled in vocational training. Strong Analytical and creative knowledge.

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