Question 1: Palette 1/40

NEET 2026 MCQ

Given below are certain reactions. Identify the reaction for which $K_P \neq K_C$.

A

$\mathrm{H}_2 \mathrm{O}(\mathrm{g})+\mathrm{CO}(\mathrm{g}) \rightleftharpoons \mathrm{H}_2(\mathrm{~g})+\mathrm{CO}_2(\mathrm{~g})$

B

$\mathrm{N}_2(\mathrm{~g})+3 \mathrm{H}_2(\mathrm{~g}) \rightleftharpoons 2 \mathrm{NH}_3(\mathrm{~g})$

C

$\mathrm{H}_2(\mathrm{~g})+\mathrm{I}_2(\mathrm{~g}) \rightleftharpoons 2 \mathrm{HI}(\mathrm{g})$

D

$\mathrm{N}_2(\mathrm{~g})+\mathrm{O}_2(\mathrm{~g}) \rightleftharpoons 2 \mathrm{NO}(\mathrm{g})$

Question 2: Palette 2/40

NEET 2025 MCQ

For the reaction $\mathrm{A}(\mathrm{g}) \rightleftharpoons 2 \mathrm{~B}(\mathrm{~g})$, the backward reaction rate constant is higher than the forward reaction rate constant by a factor of 2500 , at 1000 K.

[Given : $\mathrm{R}=0.0831 \mathrm{~L} \mathrm{~atm} \mathrm{~mol}^{-1} \mathrm{~K}^{-1}$ ]

$K_p$ for the reaction at $1000 K$ is

A

0.033

B

0.021

C

83.1

D

$2.077 \times 10^5$

Question 3: Palette 3/40

NEET 2025 MCQ

Higher yield of NO in $\mathrm{N}_2(\mathrm{~g})+\mathrm{O}_2(\mathrm{~g}) \rightleftharpoons 2 \mathrm{NO}(\mathrm{g})$ can be obtained at $\left[\Delta \mathrm{H}\right.$ of the reaction $\left.=+180.7 \mathrm{~kJ} \mathrm{~mol}^{-1}\right]$

A. Higher temperature

B. Lower temperature

C. Higher concentration of $\mathrm{N}_2$

D. Higher concentration of $\mathrm{O}_2$

Choose the correct answer from the options given below :

A

B, C, D only

B

A, C, D only

C

A, D only

D

B, C only

Question 4: Palette 4/40

NEET 2024 MCQ

At a given temperature and pressure, the equilibrium constant values for the equilibria are given below:

$\begin{aligned} & 3 \mathrm{~A}_2+\mathrm{B}_2 \rightleftharpoons 2 \mathrm{~A}_3 \mathrm{~B}, \mathrm{~K}_1 \\ & \mathrm{~A}_3 \mathrm{~B} \rightleftharpoons \frac{3}{2} \mathrm{~A}_2+\frac{1}{2} \mathrm{~B}_2, \mathrm{~K}_2 \end{aligned}$

The relation between $\mathrm{K}_1$ and $\mathrm{K}_2$ is :

A

$\mathrm{K}_1^2=2 \mathrm{~K}_2$

B

$\mathrm{K}_2=\frac{\mathrm{K}_1}{2}$

C

$\mathrm{K}_1=\frac{1}{\sqrt{\mathrm{K}_2}}$

D

$\mathrm{K}_2=\frac{1}{\sqrt{\mathrm{K}_1}}$

Question 5: Palette 5/40

NEET 2024 MCQ

For the reaction in equilibrium

$\mathrm{N}_2(\mathrm{~g})+3 \mathrm{H}_2(\mathrm{~g}) \rightleftharpoons 2 \mathrm{NH}_3(\mathrm{~g}), \Delta \mathrm{H}=-\mathrm{Q}$

Reaction is favoured in forward direction by:

A

use of catalyst

B

decreasing concentration of $\mathrm{N}_2$

C

low pressure, high temperature and high concentration of ammonia

D

high pressure, low temperature and higher concentration of $\mathrm{H}_2$

Question 6: Palette 6/40

NEET 2024 MCQ

In which of the following equilibria, $\mathrm{K}_p$ and $\mathrm{K}_{\mathrm{c}}$ are NOT equal?

A

$\mathrm{PCl}_{5(\mathrm{~g})} \rightleftharpoons \mathrm{PCl}_{3(\mathrm{~g})}+\mathrm{Cl}_{2(\mathrm{~g})}$

B

$\mathrm{H}_{2(\mathrm{~g})}+\mathrm{I}_{2(\mathrm{~g})} \rightleftharpoons 2 \mathrm{HI}_{(\mathrm{g})}$

C

$\mathrm{CO}_{(\mathrm{g})}+\mathrm{H}_2 \mathrm{O}_{(\mathrm{g})} \rightleftharpoons \mathrm{CO}_{2(\mathrm{~g})}+\mathrm{H}_{2(\mathrm{~g})}$

D

$2 \mathrm{BrCl}_{(\mathrm{g})} \rightleftharpoons \mathrm{Br}_{2(\mathrm{~g})}+\mathrm{Cl}_{2(\mathrm{~g})}$

Question 7: Palette 7/40

NEET 2024 MCQ

For the reaction $2 \mathrm{~A} \rightleftharpoons \mathrm{B}+\mathrm{C}, \mathrm{K}_{\mathrm{c}}=4 \times 10^{-3}$. At a given time, the composition of reaction mixture is: $[A]=[B]=[C]=2 \times 10^{-3} \mathrm{M} \text {. }$ Then, which of the following is correct?

A

Reaction is at equilibrium.

B

Reaction has a tendency to go in forward direction.

C

Reaction has a tendency to go in backward direction.

D

Reaction has gone to completion in forward direction.

Question 8: Palette 8/40

NEET 2024 MCQ

Consider the following reaction in a sealed vessel at equilibrium with concentrations of $\mathrm{N}_2=3.0 \times 10^{-3} \mathrm{M}, \mathrm{O}_2=4.2 \times 10^{-3} \mathrm{M}$ and $\mathrm{NO}=2.8 \times 10^{-3} \mathrm{M}$.

$2 \mathrm{NO}_{(\mathrm{g})} \rightleftharpoons \mathrm{N}_{2(\mathrm{~g})}+\mathrm{O}_{2(\mathrm{~g})}$

If $0.1 \mathrm{~mol} \mathrm{~L} \mathrm{~L}^{-1}$ of $\mathrm{NO}_{(\mathrm{g})}$ is taken in a closed vessel, what will be degree of dissociation ($\alpha$) of $\mathrm{NO}_{(\mathrm{g})}$ at equilibrium?

A

0.00889

B

0.0889

C

0.8889

D

0.717

Question 9: Palette 9/40

NEET 2023 MCQ

For a weak acid HA, the percentage of dissociation is nearly 1% at equilibrium. If the concentration of acid is 0.1 mol L$^{-1}$, then the correct option for its K$_a$ at the same temperature is :

A

$1\times10^{-4}$

B

$1\times10^{-6}$

C

$1\times10^{-5}$

D

$1\times10^{-3}$

Question 10: Palette 10/40

NEET 2022 MCQ

K_p for the following reaction is 3.0 at 1000 K.

CO₂(g) + C(s) $\rightleftharpoons$ 2CO(g)

What will be the value of K_c for the reaction at the same temperature?

(Given : R = 0.083 L bar K^$-$1 mol^$-$1)

A

3.6

B

0.36

C

3.6 $\times$ 10^$-$2

D

3.6 $\times$ 10^$-$3

Question 11: Palette 11/40

NEET 2022 MCQ

3O₂(g) $\rightleftharpoons$ 2O₃(g)

for the above reaction at 298 K, K_c is found to be 3.0 $\times$ 10^$-$59. If the concentration of O₂ at equilibrium is 0.040 M then concentration of O₃ in M is

A

4.38 $\times$ 10^$-$32

B

1.9 $\times$ 10^$-$63

C

2.4 $\times$ 10³¹

D

1.2 $\times$ 10²¹

Question 12: Palette 12/40

NEET 2018 MCQ

Which one of the following conditions will favour maximum formation of the product in the reaction
A_2(g) + B_2(g) ⇌ X_2(g) , $\Delta $_rH = –X kJ ?

A

Low temperature and high pressure

B

Low temperature and low pressure

C

High temperature and high pressure

D

High temperature and low pressure

Question 13: Palette 13/40

NEET 2017 MCQ

The equilibrium constants of the following are

N₂ + 3H₂ $\rightleftharpoons$ 2NH₃;     K₁

N₂ + O₂ $\rightleftharpoons$ 2NO;     K₂

H₂ + ${1 \over 2}$O₂ $\rightleftharpoons$ H₂O;     K₃

The equilibrium constant (K) of the reaction :

2NH₃ + ${5 \over 2}$ O₂ $\rightleftharpoons$ 2NO + 3H₂O will be

A

K₂K₃³/K₁

B

K₂K₃/K₁

C

K₂³K₃/K₁

D

K₁K₃³/K₂

Question 14: Palette 14/40

NEET 2017 MCQ

A 20 litre container at 400 K contains CO_2(g) at pressure 0.4 atm and an excess of SrO (neglect the volume of solid SrO). The volume of the container is now decreased by moving the movable piston fitted in the container. The maximum volume of the container, when pressure of CO₂ attains its maximum value, will be

(Given that : SrCO_3(s) $\rightleftharpoons$ SrO_(s) + CO_2(g), K_p = 1.6 atm)

A

10 litre

B

4 litre

C

2 litre

D

5 litre

Question 15: Palette 15/40

NEET 2016 MCQ

Consider the following liquid-vapour equilibrium.
Liquid $\rightleftharpoons$ Vapour
Which of the following relations is correct ?

A

${{d\ln P} \over {d{T^2}}} = {{ - \Delta {H_v}} \over {{T^2}}}$

B

${{d\ln P} \over {dT}} = {{\Delta {H_v}} \over {R{T^2}}}$

C

${{d\ln G} \over {d{T^2}}} = {{\Delta {H_v}} \over {R{T^2}}}$

D

${{d\ln P} \over {dT}} = {{ - \Delta {H_v}} \over {RT}}$

Question 16: Palette 16/40

NEET 2015 MCQ

If the equilibrium constant for

N_2(g) + O_2(g) $\rightleftharpoons$ 2NO_(g) is K, the equilibrium

constant for

${1 \over 2}$ N_2(g) + ${1 \over 2}$O_2(g) $\rightleftharpoons$ NO_(g) will be

A

${1 \over 2}$ K

B

K

C

K²

D

K^1/2

Question 17: Palette 17/40

NEET 2015 MCQ

If the value of equilibrium constant for a particular reaction is 1.6 $ \times $ 10¹², then at equilibrium the system will contain

A

mostly products

B

similar amounts of reactants and products

C

all reactants

D

mostly reactants.

Question 18: Palette 18/40

NEET 2015 MCQ

Which of the following statements is correct for a reversible process in a state of equilibrium?

A

$\Delta $G^o = $-$2.30 RT log K

B

$\Delta $G^o = 2.30 RT log K

C

$\Delta $G = $-$2.30 RT log K

D

$\Delta $G = 2.30 RT log K

Question 19: Palette 19/40

NEET 2014 MCQ

For the reversible reaction,
N_2(g) + 3H_2(g) $\rightleftharpoons$ 2NH_3(g) + heat

The equilibrium shifts in forward direction

A

by increasing the concentration of NH_3(g)

B

by decreasing the pressure

C

by decreasing the concentrations of N_2(g) and H_2(g)

D

by increasing pressure and decreasiing temperature.

Question 20: Palette 20/40

NEET 2014 MCQ

Using the Gibb's energy change, $\Delta $G^o = +63.3 kJ, for the following reaction,

Ag₂CO_3(s) $\rightleftharpoons$ 2 Ag⁺_(aq) + CO₃^2$-$ _(aq)
the K_sp of Ag₂CO_3(s) in water at 25^oC is
(R = 8.314 J K^$-$1 mol^$-$1)

A

3.2 $ \times $ 10^$-$26

B

8.0 $ \times $ 10^$-$12

C

2.9 $ \times $ 10^$-$3

D

7.9 $ \times $ 10^$-$2

Question 21: Palette 21/40

NEET 2014 MCQ

For a given exothermic reaction, K_p and K'_p are the equilibrium constants at temperatures T₁ and T₂, respectively. Assuming that heat of reaction is constant in temperature range between T₁ and T₂, it is readily observed that

A

K_p > K'_p

B

K_p < K'_p

C

K_p = K'_p

D

K_p = ${1 \over {k{'_p}}}$

Question 22: Palette 22/40

NEET 2012 MCQ

Given the reaction between 2 gases represented by A₂ and B₂ to give the compound AB_(g),

A₂(g) + B_2(g) $\rightleftharpoons$ 2AB_(g)

At equilibrium, the concentration of
A₂ = 3.0 $ \times $ 10^$-$3 M, of B₂ = 4.2 $ \times $ 10^$-$3 M, of AB = 2.8 $ \times $ 10^$-$3 M
If the reaction takes place in a sealed vessel at 527^oC, then the value of K_c will be

A

2.0

B

1.9

C

0.62

D

4.5

Question 23: Palette 23/40

NEET 2012 MCQ

Given that the equilibrium constant for the reaction,
2SO_2(g) + O_2(g) $\rightleftharpoons$ 2SO_3(g)
has a value of 278 at a particular temperature. What is the value of the equilibrium constant for the following reaction at the same temperature ?
SO_3(g) $\rightleftharpoons$ SO_2(g) + ${1 \over 2}$ O_2(g)

A

1.8 $ \times $ 10^$-$3

B

3.6 $ \times $ 10^$-$3

C

6.0 $ \times $ 10^$-$2

D

1.3 $ \times $ 10^$-$5

Question 24: Palette 24/40

NEET 2011 MCQ

For the reaction, N_2(g) + O_2(g) $\rightleftharpoons$ 2NO_(g), the equilibrium constant is K₁. The equilibrium constant is K₂ for the reaction,
2NO_(g) + O_2(g) $\rightleftharpoons$ 2NO_2(g)
What is K for the reaction,
NO_2(g) $\rightleftharpoons$ ${1 \over 2}$N_2(g) + O_2(g)

A

${1 \over {2{K_1}{K_2}}}$

B

${1 \over {4{K_1}{K_2}}}$

C

${\left[ {{1 \over {{K_1}{K_2}}}} \right]^{1/2}}$

D

${1 \over {{K_1}{K_2}}}$

Question 25: Palette 25/40

NEET 2011 MCQ

The value of $\Delta $H for the reaction
X_2(g) + 4Y_2(g) $\rightleftharpoons$ 2XY_4(g)
is less than zero. Formation of XY_4(g) will be favoured at

A

high temperature and high pressure

B

low pressure and low temperature

C

high temperature and low pressure

D

high pressure and low temperature

Question 26: Palette 26/40

NEET 2010 MCQ

The reaction,
2A_(g) + B_(g) $\rightleftharpoons$ 3C_(g) + D_(g)
is begun with the concentrations of A and B both at an initial value of 1.00 M. When equilibrium is reached, the concentration of D is measuread and found to be 0.25 M. The value for the equilibrium constant for this reaction is given by the expression

A

[(0.75)³ (0.25)] $ \div $ [(1.00)² (1.00)]

B

[(0.75)³ (0.25)] $ \div $ [(0.50)² (0.75)]

C

[(0.75)³ (0.25)] $ \div $ [(0.50)² (0.25)]

D

[(0.75)³ (0.25)] $ \div $ [(0.75)² (0.25)]

Question 27: Palette 27/40

NEET 2010 MCQ

In which of the following equilibrium K_c and K_p are not equal?

A

2NO_(g) $\rightleftharpoons$ N_2(g) + O_2(g)

B

SO_2(g) + NO_2(g) $\rightleftharpoons$ SO_3(g) + NO_(g)

C

H_2(g) + I_2(g) $\rightleftharpoons$ 2HI_(g)

D

2C_(s) + O_2(g) $\rightleftharpoons$ 2CO_2(g)

Question 28: Palette 28/40

NEET 2009 MCQ

The dissociation constants for acetic acid and HCN at 25^oC are 1.5 $ \times $ 10^$-$5 and 4.5 $ \times $ 10^$-$10 respectively. The equilibrium constant for the equilibrium
CN^$-$ + CH₃COOH $\rightleftharpoons$ HCN + CH₃COO^$-$ would be

A

3.0 $ \times $ 10^$-$5

B

3.0 $ \times $ 10^$-$4

C

3.0 $ \times $ 10⁴

D

3.0 $ \times $ 10⁵

Question 29: Palette 29/40

NEET 2008 MCQ

The values of for the reactions,

X $\rightleftharpoons$ Y + Z      . . . .(i)
A $\rightleftharpoons$ 2B       . . . .(ii)

are in the ratio 9 : 1. If degree of dissociation of X and A be equal, then total pressure at equilibrium (i) and (ii) are in the ratio

A

36 : 1

B

1 : 1

C

3 : 1

D

1 : 9

Question 30: Palette 30/40

NEET 2008 MCQ

The dissociation equilibrium of a gass AB₂ can be represented as :
2AB_2(g) $\rightleftharpoons$ 2AB_(g) + B_2(g)
The degree of dissociation is x and is small compared to 1. The expression relating the degree of dissociation (x) with equilibrium constant K_p and total pressure P is

A

(2K_p/P)^1/2

B

(K_p/P)

C

(2K_p/P)

D

(2K_p/P)^1/3

Question 31: Palette 31/40

NEET 2008 MCQ

The value of equilibrium constant of the reaction
HI_(g) $\rightleftharpoons$ ${1 \over 2}$H_2(g) + ${1 \over 2}$I_2(g)
is 8.0. The The equilibrium constant of the reaction
H_2(g) + I_2(g) $\rightleftharpoons$ 2HI_(g) will be

A

16

B

1/8

C

1/16

D

1/64

Question 32: Palette 32/40

NEET 2008 MCQ

If the concentration of OH^$-$ ions in the reaction
Fe(OH)_3(s) $\rightleftharpoons$ Fe³⁺_(aq) + 3OH^$-$_(aq)
is decreased by 1/4 times, then equilibrium concentration of Fe³⁺ will increase by

A

64 times

B

4 times

C

8 times

D

16 times

Question 33: Palette 33/40

NEET 2007 MCQ

The equilibrium constants of the following are

N₂ + 3H₂ $\rightleftharpoons$ 2NH₃;     K₁

N₂ + O₂ $\rightleftharpoons$ 2NO;     K₂

H₂ + ${1 \over 2}$O₂ $\rightleftharpoons$ H₂O;     K₃

The equilibrium constant (K) of the reaction :

2NH₃ + ${5 \over 2}$ O₂ $\rightleftharpoons$ 2NO + 3H₂O will be

A

K₂K₃³/K₁

B

K₂K₃/K₁

C

K₂³K₃/K₁

D

K₁K₃³/K₂

Question 34: Palette 34/40

NEET 2006 MCQ

For the reaction :
CH4_(g) + 2O_2(g) $\rightleftharpoons$ CO_2(g) + 2H₂O_(l),
$\Delta $H_r = $-$ 170.8 kJ mol^$-$1.
Which of the following statements is not true?

A

The reaction is exothermic.

B

At equilibrium, the concentrations of CO_2(g) and H₂O_(l) are not equal.

C

The equilibrium constant for the reaction is given by K_p = ${{\left[ {C{O_2}} \right]} \over {\left[ {C{H_4}} \right]\left[ {{O_2}} \right]}}$

D

Addition of CH_4(g) or O_2(g) at equilibrium will cause a shift to the right.

Question 35: Palette 35/40

NEET 2005 MCQ

Equilibrium constants K₁ and K₂ for the following equilibriam:


are related as

A

K₂ = 1/K₁²

B

K₂ = K₁²

C

K₂ = 1/K₁

D

K₂ = K₁/2

Question 36: Palette 36/40

NEET 2003 MCQ

The reaction quotient (Q) for the reaction

N_2(g) + 3H_2(g) $\rightleftharpoons$ 2NH_3(g) is given by

$Q = {{{{\left[ {N{H_3}} \right]}^2}} \over {\left[ {{N_2}} \right]{{\left[ {{H_2}} \right]}^3}}}$.

The reaction will proceed from right to left if

A

Q = K_c

B

Q < K_c

C

Q > K_c

D

Q = 0

Question 37: Palette 37/40

NEET 2003 MCQ

The equilibrium constants of the following are

N₂ + 3H₂ $\rightleftharpoons$ 2NH₃;     K₁

N₂ + O₂ $\rightleftharpoons$ 2NO;     K₂

H₂ + ${1 \over 2}$O₂ $\rightleftharpoons$ H₂O;     K₃

The equilibrium constant (K) of the reaction :

2NH₃ + ${5 \over 2}$ O₂ $\rightleftharpoons$ 2NO + 3H₂O will be

A

K₂K₃³/K₁

B

K₂K₃/K₁

C

K₂³K₃/K₁

D

K₁K₃³/K₂

Question 38: Palette 38/40

NEET 2002 MCQ

Reaction BaO_2(g) $\rightleftharpoons$ BaO_(s) + O_2(g); $\Delta $H = +ve. In equilibrium condition, pressure of O₂ depends on

A

increase mass of BaO₂

B

increase mass of BaO

C

increase temperature on equilibrium

D

increase mass of BaO₂ and BaO both.

Question 39: Palette 39/40

NEET 2000 MCQ

Equilibrium constant K_p for following reaction
MgCO_3(s) $\rightleftharpoons$ MgO_(s) + CO_2(g)

A

K_p = P_CO2

B

K_p = P_CO2 $ \times $ ${{{P_{C{O_2}}} \times {P_{MgO}}} \over {{P_{MgC{O_3}}}}}$

C

K_p = ${{{P_{C{O_2}}} + {P_{MgO}}} \over {{P_{MgC{O_3}}}}}$

D

K_p = ${{{P_{MgC{O_3}}}} \over {{P_{C{O_2}}} + {P_{MgO}}}}$

Question 40: Palette 40/40

NEET 2000 MCQ

For any reversible reaction, if we increase concentration of the reactants, then effect on equilibrium constant

A

depends on amount of concentration

B

unchange

C

decrease

D

increase