Use data from Appendix IIB to calculate the equilibrium constants at $25^{\circ} \mathrm{C}$ for each reaction. $\Delta G_{\mathrm{f}}^{\circ}$ for BrCl $(g)$ is $-1.0 \mathrm{kJ} / \mathrm{mol}$ .
\begin{equation}\begin{array}{l}{\text { a. } 2 \mathrm\ {NO}_{2}(g) \Longrightarrow \mathrm{N}_{2} \mathrm{O}_{4}(g)} \\ {\text { b. } \mathrm{Br}_{2}(g)+\mathrm{Cl}_{2}(g) \rightleftharpoons 2 \mathrm\ {BrCl}(g)}\end{array}\end{equation}