Chapter 12 - Chemical Equilibrium - Questions for Review and Thought - Topical Questions - Page 523b: 32

$K_{c}=0.0161$

$K_{p}=K_{c}(RT)^{\Delta n}\implies K_{c}=\frac{K_{p}}{(RT)^{\Delta n}}$ $K_{p}=P_{H_{2}O}=0.467\,atm$ $\Delta n=1-0=1$ $T=(273+80)\,K=353\,K$ $R=0.0821\,L\,atm\,K^{-1}mol^{-1}$ $\implies K_{c}=\frac{0.467}{(0.0821\times353)^{1}}=0.0161$