## What is the formula of magnesium nitride, \(M g_{3} N_{2} ?\)

Answer:

Consider the typical valencies of magnesium metal and dinitrogen in their compounds.

Explanation:

Magnesium is a Group 2 metal with 2 valence electrons that can be oxidized:

\(M g \rightarrow M g^{2+}+2 e^{-}\).

Dinitrogen is a gaseous non-metal that can be reduced to \(N^{3-}:\) Each nitrogen ATOM has 5 valence electrons, and this configuration can be reduced to \(N^{3-}:\).

\(\frac{1}{2} N_{2}(g)+3 e^{-} \rightarrow N^{3-}\).

Since typically non-metals can oxidize metals, or metals reduce non-metals, we cross multiply to give the stoichiometric equation:

\(3 M g(s)+N_{2}(g) \rightarrow M g_{3} N_{2}(s)\).

Such a reaction is called a nitriding reaction. It would require conditions of high temperature.