In which of the following equilibria, K p and K c are NOT equal?

PCl 5( g ) rightleftharpoons PCl 3( g ) + Cl 2( g )

H 2( g ) + I 2( g ) rightleftharpoons 2 HI ( g )

CO ( g ) + H 2 O ( g ) rightleftharpoons CO 2( g ) + H 2( g )

2 BrCl ( g ) rightleftharpoons Br 2( g ) + Cl 2( g )

Chemistry · Chemical Equilibrium

NEET (UG) 2024 — Question 60

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

Option A:
$\mathrm{PCl}_{5(\mathrm{~g})} \rightleftharpoons \mathrm{PCl}_{3(\mathrm{~g})}+\mathrm{Cl}_{2(\mathrm{~g})}$
Correct
Option B:
$\mathrm{H}_{2(\mathrm{~g})}+\mathrm{I}_{2(\mathrm{~g})} \rightleftharpoons 2 \mathrm{HI}_{(\mathrm{g})}$
Option C:
$\mathrm{CO}_{(\mathrm{g})}+\mathrm{H}_{2} \mathrm{O}_{(\mathrm{g})} \rightleftharpoons \mathrm{CO}_{2(\mathrm{~g})}+\mathrm{H}_{2(\mathrm{~g})}$
Option D:
$2 \mathrm{BrCl}_{(\mathrm{g})} \rightleftharpoons \mathrm{Br}_{2(\mathrm{~g})}+\mathrm{Cl}_{2(\mathrm{~g})}$

$K_{p}=K_{c}(R T)^{\Delta n_{g}}$

for $K_{p} \neq K_{c}$ ,

\Delta \mathrm{n}_{\mathrm{g}} \neq 0

$\Delta n_{g}=n_{p}-n_{r}$

(1) $\Delta \mathrm{n}_{\mathrm{g}}=2-1=1$

(2) $\Delta \mathrm{n}_{\mathrm{g}}=2-2=0$

(3) $\Delta \mathrm{n}_{\mathrm{g}}=2-2=0$

(4) $\Delta n_{g}=2-2=0$

Answer key and solution verified before publishing.

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Exam: NEET (UG) 2024
Paper: 2024 paper
Subject: Chemistry
Chapter: Chemical Equilibrium
Topic: Analysis of Chemical Equilibrium, Equilibrium Constant and Reaction Quotient