Question

How does hydrogen resemble in electronic configuration with that of halogen?

Answer 1

Halogens are short of one electron to achieve noble gas configuration and to acquire stability.

$\underset{\left(2,8,7\right)}{\mathrm{Cl}}+1{\mathrm{e}}^{-}\to \underset{\left(2,8,8\right)}{{\mathrm{Cl}}^{-}}$

Similarly, hydrogen is also short of one electron to achieve noble gas configuration and acquire stability.

$\underset{\left(1\right)}{\mathrm{H}}+1{\mathrm{e}}^{-}\to \underset{\left(2\right)}{{\mathrm{H}}^{-}}$