Question

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

• A. $2NO\left(g\right)\rightleftharpoons N_2\left(g\right)+O_2\left(g\right)$
• B. $S{O}_2\left(g\right)+N{O}_2\left(g\right)\rightleftharpoons S{O}_3\left(g\right)+NO\left(g\right)$
• C. $H_2\left(g\right)+I_2\left(g\right)\rightleftharpoons 2HI\left(g\right)$
• D. $2C\left(s\right)+O_2\left(g\right)\rightleftharpoons 2C{O}_2\left(g\right)$

Answer 1

The correct option is D $2C\left(s\right)+O_2\left(g\right)\rightleftharpoons 2C{O}_2\left(g\right)$

$K_p$ and $K_c$ are related as:
$K_p=K_c(RT{)}^{\Delta n_g}$
If $\Delta n_g=0$, $K_p=K_c$
(a) $\Delta n_g=0$
(b) $\Delta n_g=0$
(c) $\Delta n_g=0$
(d) $\Delta n_g=2-1=1$
Hence, $K_p\ne K_c$