Chapter 17 - Sections 17.1-17.9 - Exercises - Problems by Topic - Page 855: 77

4.8

$\ln \frac{K_{2}}{K_{1}}=-\frac{\Delta H^{\circ}_{rxn}}{R}(\frac{1}{T_{2}}-\frac{1}{T_{1}})$ $=-\frac{-25.8\times10^{3}\,J/mol}{8.314\,Jmol^{-1}K^{-1}}(\frac{1}{655\,K}-\frac{1}{298\,K})$ $=-5.67571$ $\frac{K_{2}}{K_{1}}=e^{-5.67571}=0.003428$ $\implies K_{2}=K_{1}\times0.003428=1.4\times10^{3}\times0.003428$ $=4.8$