Comment on each of the following observations:
Lithium is the only alkali metal to form a nitride directly.
Unlike the other elements of group 1, Li reacts directly with nitrogen to form lithium nitride. This is because Li+ is very small in size and so its size is the most compatible with the N3– ion. Hence, the lattice energy released is very high. This energy also overcomes the high amount of energy required for the formation of the N3– ion.
Due to its smaller size lithium can form nitride directly.