Chapter 18.6, Problem 18.8E

Use the data from Table 18.2 to obtain the equilibrium constant K_p at 25°C for the reaction

${\text{CaCO}}_3(s)\underset{}{\rightleftharpoons }\text{CaO}(s)+{\text{CO}}_2(g)$

Note that values of $\Delta G_f^{°}$ are needed for CaCO₃ and CaO, even though the substances do not appear in $Kp=P_{{\text{CO}}_2}$.