Formation Oxide From Oxygen Requires First Exothermic Then Endothermic Step Shown Below

The formation of the oxide ion, 02-(g), from oxygen atom requires first an exothermic and … – ion has comparatively smaller size than…


(c) There is a lot of repulsion when similar charges approach each other as
O(g), and electron are both negatively charged. To add an electron under such situation, the force of repulsion is to be overcome by applying external energy.