Question

In the nitrogen family what is the order of electron affinity values with sign is it positive for all members of 15th group

Answer 1

Atoms	Electron gain enthalpy
N	8
P	-72
As	-78
Sb	-103

1. For the first member in this group, electron gain enthalpy is positive.
2. Because of small size of Nitrogen, ia it has high a electron density.
3. .an Hence when an electron is added to Nitrogen, the electron is strongly repelled, therefore a small amount of energy has to be supplied to add the electron.
4. .Even though P, As, and Sb each have $P{}^3$ configuration stable but as size increases extensively, so electron capture becomes much easy, due to decreased electron density and energy is released.