Question

For the reaction, $2N{O}_2\left(g\right)\leftrightharpoons 2NO\left(g\right)+O_2\left(g\right),(K_C=1.8\times {10}^{-6}at{184}^{\circ }C)$
(R = 0.0831 kJ/(mol.K))
when $K_p$ and $K_c$ are compared at ${184}^{\circ }C$ it is found that

• A. whether $K_p$ is greater than, less than or equal to $K_c$ depends upon the total gas pressure
• B. $K_p=K_c$
• C. $K_p$ is less than $K_c$
• D. $K_p$ is greater than $K_c$

Answer 1

The correct option is D $K_p$ is greater than $K_c$

As we know
$K_p=K_c(RT{)}^{△n}$
For the reaction $2N{O}_{2\left(g\right)}\leftrightharpoons 2N{O}_{\left(g\right)}+O_{2\left(g\right)}△n_0=n_R-n_P=3-2=1$
Given, $K_C=1.8\times {10}^{-6}$
$T={184}^{\circ }C$ or 457 K
On substituting the values;
$K_P=K_C\times (0.0831\times 457{)}^1$
So $K_p>K_c$