Magnesium sulfide is composed of magnesium, a metal, and sulfur, a nonmetal. When a metal and a nonmetal react, the metal will lose electrons to the nonmetal, resulting in the formation of positively charged metal ions and negatively charged nonmetal ions. These ions are then attracted to each other by electrostatic forces, forming an ionic compound. In the case of magnesium sulfide, the magnesium atoms lose two electrons each, while the sulfur atoms gain two electrons each, resulting in the formation of magnesium ions (Mg²⁺) and sulfide ions (S²⁻). These ions are then attracted to each other to form magnesium sulfide (MgS), an ionic compound.