The process requiring absorption of energy is:

Options

A. `N to N^(-)`
B. `F to F^(-)`
C. `Cl to Cl^(-)`
D. `H to H^(-)`

Answer

A

Explanation

Nitrogen has stable `2p^(3)` configuraiton and also due to high `e^(-)` charge density at outermost orbital it requires energy to add one extra `e^(-)` in its outer most shell i.e., its first electron gain enthalpy is positive.