Final answer:
The ions in MgS are Mg²⁺ with a 2+ charge and S²⁻ with a 2- charge, making option A correct. The charges must balance to form a neutral compound.
Step-by-step explanation:
In the compound MgS, the ions and their charges are Mg²⁺ and S²⁻. Magnesium (Mg) forms a cation with a 2+ charge because it donates two electrons, and sulfur (S) forms an anion with a 2- charge because it accepts two electrons. Hence, the correct answer is A) Mg²⁺ and S²⁻. In ionic compounds, the total number of positive charges must equal the total number of negative charges to create a neutral compound. This is why in the case of MgS, one Magnesium ion with a 2+ charge pairs with one Sulfide ion with a 2- charge to maintain electrical neutrality.