Question

We cannot measure the second electron affinity of oxygendirectly:
O- (g) + e - ----> O2- (g) EA2=?
The oxygen ion can exist in the solid state, but where the highenergy requirement for its formation is offset by the large latticeenergies of ionic oxides.
(a) Show that EA2 can be calculated from the enthalpy of formationand lattice energy of MgO(s), enthalpy of sublimation of Mg (s),bond energy of O2 and EA for O (g).
(b) The lattice energy of MgO is -3925 kJ/mol. Combine this withother values in the text to estimate EA2 for oxygen. Include BornHaber Cycle DDiagram