Which of the following is incorrect ?

Options

A. Li is the only alkali metal that reacts with `N_(2)` to form a nitride.
B. Li nitride is a colorless covalent solid.
C. Li nitride decomposes to the elements on heating to a high temperature.
D. Li nitride gives ammonia on reaction with water.

Answer

B

Explanation

Lithium nitride, `Li_(3)N, "is ionic" (3Li^(+) "and" N_(3)^(-))` and is ruby red. It takes `2125 "kJ mol"^(-)` of energy to form `N_(3)^(-)`. Thus, ionic nitrides are formed only by metals which have low ionization enthalpies and can form nitrides with high lattice enthalpies : `Li_(3)N, Be_(3)N_(2). Mg_(3)N_(2), Ca_(3)N_(2)`.
`2Li_(3)N overset(Heat)to 6Li+N_(2)`
`(Li^(+))N^(3-)+overset(delta+)3H-overset(delta -)OH to 3LiOH+NH_(3)`