Chapter 12, Problem 31QRT

Given these data at a certain temperature,

$\begin{array}{l}2{\text{H}}_2\left(\text{g}\right)+{\text{O}}_2\left(\text{g}\right)\rightleftharpoons 2{\text{H}}_2\text{O}\left(\text{g}\right)K_{\text{c}}=3.2\times {10}^{81}\\ {\text{N}}_2\left(\text{g}\right)+3{\text{H}}_2\left(\text{g}\right)\rightleftharpoons 2{\text{NH}}_3\left(\text{g}\right)K_{\text{c}}=3.5\times {10}^8\end{array}$

calculate K_c for the reaction of ammonia with oxygen to give N₂(g) and H₂O(g).