The formula for lithium nitride is Li3N.
This chemical compound consists of three lithium (Li) ions and one nitride (N) ion. Lithium, being an alkali metal, has a single valence electron that it readily loses to form a cation. On the other hand, nitrogen, since it is in group 15 of the periodic table, typically gains three electrons to achieve a stable electronic configuration, forming a nitride ion with a -3 charge. To balance the charges, three lithium ions (each with a +1 charge) combine with one nitride ion (with a -3 charge), resulting in the formula Li3N.