Question Detail
Question
The formula for a compound is written based on the charges of its constituent ions to ensure electrical neutrality. If a cation has a charge of +2 and an anion has a charge of -1, what is the correct formula for the compound?
Correct Answer
Option B is the correct answer.
Detailed Explanation
To balance the charges, the total positive charge must equal the total negative charge. For a +2 cation and a -1 anion, two anions are needed to balance the +2 charge of one cation. The resulting formula is A2+ (B-)2, which simplifies to AB2 (where A is the cation and B is the anion).
Hint
The subscript on the anion becomes the charge on the cation, and the subscript on the cation becomes the charge on the anion, then simplify if needed.