Solution:The given statement is true.
Concept: Metal nitrides decompose to metal hydroxide and ammonia on treatment with water.
Nitride is an ion of nitrogen in the -3 oxidation state. Magnesium hydroxide decomposes to its hydroxide and ammonia. This is a common reaction for metal nitrides.
The reaction is as follows;
The can be identified by its solubility in sodium hydroxide. Both magnesium nitride and hydroxide are soluble in . While lead hydroxide dissolves in . This is used to distinguish between them.
The ammonia produced can be identified by treating it with . To the gas produced, a glass rod dipped in is shown. which produces dense white vapours of on this test.
Hence, the correct answer is option 1.