Question

The equilibrium between gaseous isomers A, B and C can be represented as:

$A\left(g\right)\rightleftharpoons B\left(g\right)$	$K_1=?$
$B\left(g\right)\rightleftharpoons C\left(g\right)$	$K_2=0.4$
$C\left(g\right)\rightleftharpoons A\left(g\right)$	$K_3=0.6$

• A. [A]+[B]+[C]=1 M at any time of reactions
• B. Concentration of C is 4.1 M at the attainment equilibrium in all reactions
• C. The value of $K_1$ is $\frac{1}{0.24}$
• D. Isomer [A] is least stable as per thermodynamics

Answer 1

Answer: (C), (D)

The correct options are
C The value of $K_1$ is $\frac{1}{0.24}$
D Isomer [A] is least stable as per thermodynamics

The reaction $A\left(g\right)\rightleftharpoons B\left(g\right)$ is obtained when the two reactions, $B\left(g\right)\rightleftharpoons C\left(g\right)$ and $C\left(g\right)\rightleftharpoons A\left(g\right)$ are reversed and added.

$B\rightleftharpoons C$ $K_2$

$C\rightleftharpoons A$ $K_3$

On adding both the equation and reversing it,

$A\rightleftharpoons B$ $K=\frac{1}{K_2\times K_3}$

Hence, $K=\frac{1}{K_2\times K_3}=\frac{1}{0.4\times 0.6}=\frac{1}{0.24}$

The value of the equilibrium constant for the reaction $A\left(g\right)\rightleftharpoons B\left(g\right)$ is maximum.

Hence, isomer A is least stable as per thermodynamics.