Would you expect the second electron gain enthalpy of 0 as positive

CBSE Class 11 CBSE Class 11 Chemistry
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1

Would you expect the second electron gain enthalpy of 0 as positive, more negative or less negative than the first? Justify you answer.

2

O + ${{e}^{-}}$ ----------> ${{O}^{-}}$ ; ∆H = -141 KJ / ${{mol}^{-1}}$
O + ${{e}^{-}}$ ----------> ${{O}^{2-}}$ ; ∆H = + 780 KJ / ${{mol}^{-1}}$
When an electron is added to oxygen atom to form ion, energy is released. Hence, first electron gain enthalpy of oxygen is negative.
But when another electron is added to ${{O}^{-}}$ ion to form ${{O}^{2-}}$ ion, it feels stronger electrostatic repulsion. Hence, addition of second electron takes place with absorption of energy. That’s why the second electron gain enthalpy of oxygen is positive.