Final answer:
The chemical formula for magnesium nitride is Mg3N2, formed from magnesium ions (Mg2+) and nitride ions (N3-).
Step-by-step explanation:
The chemical formula for the chemical magnesium nitride is Mg3N2. When magnesium and nitrogen react to form an ionic compound, magnesium forms a cation, and nitrogen forms an anion. Magnesium, being in group 2 of the periodic table, loses two electrons to form a Mg2+ ion, known as a magnesium ion. Nitrogen, on the other hand, gains three electrons to achieve a stable octet similar to the noble gas neon, forming an N3- ion, known as a nitride ion.
Combining the magnesium cation and the nitrogen anion to form an ionic compound, we need to balance the charges so that the resulting compound is electrically neutral. Since the charges of Mg2+ and N3- are +2 and -3 respectively, we need three Mg2+ ions and two N3- ions to balance the charges, resulting in the formula Mg3N2.