Which of following elements does not form amide when reacted with ammonia?

Step-by-step solution

Lithium doesn’t from amide when reacted with ammonia. It forms tetraammielithium, L i N H 3 4 . The equation for the reaction is as follows: L i + 4 N H 3 → L i N H 3 4 T e t r a a m n i n e l i t h i u m