Chapter 6, Problem 6.96SP

Use the following information plus the data given in Tables6.2 and 6.3 to calculate the second electron affinity, $E_{\text{ea2}}$ , of oxygen. Is the ${\text{O}}^{\text{2}-}$ ion stable in the gas phase? Why is its table in solid MgO?
$\begin{array}{l}\text{Heat of sublimation for Mg}\left(\text{s}\right)=+\text{147}.\text{7 kJ}/\text{mol}\\ {\text{Bond dissociation energy for O}}_{\text{2}}\left(\text{g}\right)=+\text{498}.\text{4 kJ}/\text{mol}\\ E_{\text{ea1}}\text{for O}\left(g\right)=-\text{141}.0\text{ kJ}/\text{mol}\\ \text{Net energy change for formation of MgO}\left(s\right)\text{ from its elements}=-\text{6}0\text{1}.\text{7 kJ}/\text{mol}\end{array}$