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For a reaction, \( \mathrm{N_2O_5(g)} \rightarrow 2\,\mathrm{NO_2(g)} + \tfrac{1}{2}\,\mathrm{O_2(g)} \) in a constant volume container, no products were present initially. The final pressure of the system when \( 50\% \) of reaction gets completed is:

For the reaction, \( \mathrm{H_2(g)} + \mathrm{I_2(g)} \rightleftharpoons 2\,\mathrm{HI(g)} \)
Attainment of equilibrium is predicted correctly by:

Ice and water are placed in a closed container at a pressure of \( 1 \, \text{atm} \) and temperature \( 273.15 \, \text{K} \). If pressure of the system is increased \( 2 \) times, keeping temperature constant, then identify correct observation from following:

\( 37.8 \ \mathrm{g} \ \mathrm{N_2O_5} \) was taken in a \( 1 \ \mathrm{L} \) reaction vessel and allowed to undergo the following reaction at \( 500 \ \mathrm{K} \)
\( 2 \ \mathrm{N_2O_5(g)} \rightleftharpoons 2 \ \mathrm{N_2O_4(g)} + \mathrm{O_2(g)} \)
The total pressure at equilibrium was found to be \( 18.65 \ \mathrm{bar} \).
Then, \( K_p = \_\_\_\_\_\_\_\_\_\_ \times 10^{-2} \) [nearest integer] Assume \( \mathrm{N_2O_5} \) to behave ideally under these conditions.
Given: \( R = 0.082 \ \mathrm{bar \ L \ mol^{-1} \ K^{-1}} \)

A vessel at \( 1000 \, \text{K} \) contains \( \mathrm{CO_2} \) with a pressure of \( 0.5 \, \text{atm} \). Some of \( \mathrm{CO_2} \) is converted into \( \mathrm{CO} \) on addition of graphite. If total pressure at equilibrium is \( 0.8 \, \text{atm} \), then \( K_p \) is:

Consider the following chemical equilibrium of the gas phase reaction at a constant temperature: \( \mathrm{A(g)} \rightleftharpoons \mathrm{B(g)} + \mathrm{C(g)} \).
If \( p \) being the total pressure, \( K_p \) is the pressure equilibrium constant and \( \alpha \) is the degree of dissociation, then which of the following is true at equilibrium?

At temperature $T$, compound $\text{AB}_{2(g)}$ dissociated as $\text{AB}_{2(g)} \rightleftharpoons \text{AB}_{(g)} + \frac{1}{2}\text{B}_{2(g)}$ having degree of dissociation $x$ (small compared to unity). The correct expression for $x$ in terms of $\text{K}_\text{p}$ and $p$ is

Consider the following equilibrium, \( \mathrm{CO(g)} + 2\mathrm{H_2(g)} \rightleftharpoons \mathrm{CH_3OH(g)} \). \( 0.1 \) mol of \( \mathrm{CO} \) along with catalyst is present \( 2 \, \mathrm{dm^3} \) flask maintained at \( 500 \, \mathrm{K} \).
Hydrogen is introduced into the flask until the pressure is \( 5 \, \mathrm{bar} \) and \( 0.04 \) mol of \( \mathrm{CH_3OH} \) is formed. The \( K_p \) is ________ \( \times 10^{-3} \) (nearest integer).
Given; \( R = 0.08 \, \mathrm{dm^3 \, bar \, K^{-1} \, mol^{-1}} \).
Assume only methanol is formed as the product and the system follows ideal gas behaviour.

In the following system, \( \mathrm{PCl_5(g)} \rightleftharpoons \mathrm{PCl_3(g)} + \mathrm{Cl_2(g)} \) at equilibrium, upon addition of xenon gas at constant \( T \) and \( P \), the concentration of:

Consider the equilibrium
\( \mathrm{CO(g) + 3H_2(g) \rightleftharpoons CH_4(g) + H_2O(g)} \)
If the pressure applied over the system increases by two fold at constant temperature then
(A) Concentration of reactants and products increases.
(B) Equilibrium will shift in forward direction.
(C) Equilibrium constant increases since concentration of products increases.
(D) Equilibrium constant remains unchanged as concentration of reactants and products remain same.
Choose the correct answer from the options given below:

Given below are two statements:
Statement I : A catalyst cannot alter the equilibrium constant \( (K_c) \) of the reaction, temperature remaining constant.
Statement II : A homogenous catalyst can change the equilibrium composition of a system, temperature remaining constant.
In the light of the above statements, choose the correct answer from the options given below:

The equilibrium constant for decomposition of
\( \mathrm{H_2O(g)} \rightleftharpoons \mathrm{H_2(g)} + \tfrac{1}{2}\mathrm{O_2(g)}\)
\( (\Delta G^\circ = 92.34 \, \text{kJ mol}^{-1}) \) is \( 8.0 \times 10^{-3} \) at \( 2300 \, \text{K} \) and total pressure at equilibrium is \( 1 \, \text{bar} \). Under this condition, the degree of dissociation \( (\alpha) \) of water is ______ \( \times 10^{-2} \). (Nearest integer value)
[Assume \( \alpha \) is negligible with respect to \( 1 \)]

Consider the reaction: \( \mathrm{X_2Y(g) \rightleftharpoons X_2(g) + \tfrac{1}{2}Y_2(g)} \)
The equation representing correct relationship between the degree of dissociation \( x \) of \( \mathrm{X_2Y(g)} \) with its equilibrium constant \( K_p \) is __________. Assume \( x \) to be very very small.

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JEE Main 2025 24th Jan Evening Shift

For the reaction, \( \mathrm{H_2(g)} + \mathrm{I_2(g)} \rightleftharpoons 2\,\mathrm{HI(g)} \)
Attainment of equilibrium is predicted correctly by: