The metal that forms nitride by reacting directly with $\mathrm{N}_{2}$ of air is

JEE Main · 2019 · 09 Jan 2019 · Shift 2 · s-Block Elements

The metal that forms nitride by reacting directly with

N_{2}

of air is

Answer: (B)

Lithium is the odd one out among the alkali metals: it alone combines directly with atmospheric nitrogen,

6 Li + N X_{2} 2 Li X_{3} N

. Its very small size and high charge density let it polarise and split the strong

N \equiv N

bond, something the larger

K

Rb

and

Cs

cannot manage.

JEE Main · 2019 · 09 Jan 2019 · Shift 2 · Single correct option