Nitrogen -3 Compounds Nitrides and Ammonia

The nitrides and ammonia (including the ammonium salts) are the two major types of compounds in which nitrogen has a —3 oxidation state. The nitrides can be divided into ionic, covalent, and interstitial types in the same way as we saw earlier for the hydrides, oxides, and carbides. There are only a few ionic nitrides, the most important being those of lithium, the alkaline-earth metals, and zinc. These are prepared by direct reaction of the elements and readily hydrolyze to ammonia. 

Note that the ion is acting as a Bronsted-Lowry base in this reaction. 

The transition metals often form interstitial, nonstoichiometric nitrides in which nitrogen atoms occupy holes in the close-packed metal lattices. 

Sore Nitrogen oxidation state = -3 Name Ammonia 

Physical description Colorless gas with pungent odor weak base in aqueous solution 

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