Question

How do you name the compound `Ca_3N_2`?

Answer 1

`"Calcium nitride"`

Explanation:

As a Group 2 metal, calcium commonly forms a `Ca^(2+)` ion.

Nitrogen, in exceptional cirecumstances, can form a `N^(3-)` ion.

When `"calcium nitride"` forms (for instance when calcium is heated under dinitrogen), the ionic solid must be electrostatically neutral, i.e. `3xxCa^(2+) + 2xxN^(3-)` combine to give a neutral salt.