Question

Consider the reactions

$\frac{1}{2}N_{2}+O_{2}\rightleftharpoons NO_{2}$ $K_{1}$

$2NO_{2}\rightleftharpoons N_{2}O_{4}$ $K_{2}$

Using above equations, write down expression for K of the following reaction

$N_{2}O_{4}\rightleftharpoons N_{2}+2O_{2}$ K

• A. $K_{1}K_{2}$
• B. $\frac{K_{2}^{2}}{K_{1}}$
• C. $\frac{1}{K_{1} K_{2}^{2}}$
• D. $\frac{1}{K_{1}^{2} K_{2}}$

Answer 1

Answer: (D)

$K_{1}=\frac{\left[\right. N O_{2} \left]\right.}{\left[\right. N_{2} \left]\right.^{1 / 2} \left[\right. O_{2} \left]\right.}$ …(i)

$K_{2}=\frac{\left[\right. N_{2} O_{4} \left]\right.}{\left[\right. N O_{2} \left]\right.^{2}}$ …(ii)

$K=\frac{\left[\right. N_{2} \left]\right. \left[\right. O_{2} \left]\right.^{2}}{\left[\right. N_{2} O_{4} \left]\right.}$ …(iii)

Considering equation (i), (ii) and (iii)

$K=\frac{1}{K_{1}^{2} K_{2}}$ .