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Relation between Kp, degree of dissociation and total pressure for a gas dissociation

This type of question, asked 7 times: 14 Jun 2022, 31 Jan 2024, 23 Jan 2025, 29 Jan 2025, 2 Apr 2025, 23 Jan 2026 S1, 5 Apr 2026 S2. All 7 questions below, oldest first.

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  1. Question 1

    14 Jun 2022

    34
    For a reaction at equilibrium
    A(g)⇌B(g)+12C(g)A(g) \rightleftharpoons B(g) +\frac{1}{2}C(g)
    the relation between dissociation constant (K)(K), degree of dissociation (α)(\alpha) and equilibrium pressure (p) is given by:

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  2. Question 2

    31 Jan 2024

    131
    A(g)⇌B(g)+12C(g)A_{(g)} \rightleftharpoons B_{(g)} + \frac{1}{2}C_{(g)}. The correct relationship between KPK_{P}, α\alpha and equilibrium pressure PP is

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  3. Question 3

    23 Jan 2025

    105
    Consider the reaction
    X2Y( g)⇌X2( g)+12Y2( g)X_{2}Y(\text{ }g) \rightleftharpoons X_{2}(\text{ }g) +\frac{1}{2}Y_{2}(\text{ }g)
    The equation representing correct relationship between the degree of dissociation ( x ) of X2Y(g)X_{2}Y(g) with its equilibrium constant Kp is _____\_\_\_\_\_ . Assume x to be very very small.

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  4. Question 4

    29 Jan 2025

    29
    At temperature T , compound AB2( g)AB_{2(\text{ }g)} dissociates as AB2( g)⇌AB(g)+12 B2( g)AB_{2(\text{ }g)}\rightleftharpoons AB_{(g)}+\frac{1}{2}{\text{ }B}_{2(\text{ }g)} having degree of dissociation x (small compared to unity). The correct expression for x in terms of KpK_{p} and p is

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  5. Question 5

    2 Apr 2025

    117
    Consider the following chemical equilibrium of the gas phase reaction at a constant temperature : A(g)⇌B(g)+C(g)A(g) \rightleftharpoons B(g) + C(g).If p being the total pressure, KpK_{p} is the pressure equilibrium constant and α\alpha is the degree of dissociation, then which of the following is true at equilibrium ?

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  6. Question 6

    23 Jan 2026 S1

    47
    For the following gas phase equilibrium reaction at constant temperature,
    NH3(g)⇌12 N2(g)+32H2(g){NH}_{3}(g) \rightleftharpoons \frac{1}{2}{\text{ }N}_{2}(g) + \frac{3}{2}H_{2}(g)
    If the total pressure is 3 atm\sqrt{3}\text{ }atm and the pressure equilibrium constant (Kp)\left( K_{p} \right) is 9 atm , then the degree of dissociation is given as (x×10−2)−1/2\left( x \times 10^{- 2} \right)^{- 1/2}. The value of xx is ____\_\_\_\_ (Nearest integer)
  7. Question 7

    5 Apr 2026 S2

    31
    The reaction A(g)⇌B(g)+C(g)A(g) \rightleftharpoons B(g) + C(g) was initiated with the amount ' a ' of A(g)A(g). At equilibrium it is found that the amount of A(g)A(g) remaining is (a−x)(a - x) at a total pressure of p. The equilibrium constant KpK_{p} of the reaction can be calculated from the expression :

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