Question

1. which atom gains electrons during the formation of magnesium sulfide, shown in this equation? ·mg + :s: → mg²⁺ + :s:²⁻

Explanation:

Step1: Analyze oxidation - reduction

In a chemical reaction to form an ionic compound like magnesium sulfide ($MgS$), magnesium ($Mg$) is a metal and sulfur ($S$) is a non - metal. Metals tend to lose electrons and non - metals tend to gain electrons.

Step2: Determine electron transfer

Magnesium has 2 valence electrons and will lose 2 electrons to achieve a stable noble - gas electron configuration, forming $Mg^{2 + }$. Sulfur has 6 valence electrons and needs to gain 2 electrons to achieve a stable noble - gas electron configuration, forming $S^{2-}$.

Answer:

Sulfur ($S$)