What is the correct name for the ionic compound with the formula MgSO_3?

• A. Magnesium thiosulfate
• B. Magnesium sulfur trioxide
• C. Magnesium sulfite
• D. Magnesium sulfate

Answer: (C)

Verified step by step guidance

1. Identify the cation and anion in the compound MgSO_3. The cation is Mg^{2+} (magnesium ion) and the anion is SO_3^{2-}.
2. Recognize that SO_3^{2-} is the sulfite ion, which is different from sulfate (SO_4^{2-}) and thiosulfate (S_2O_3^{2-}).
3. Recall the naming convention for ionic compounds: the cation name is stated first (magnesium), followed by the anion name without the word 'ion'.
4. Since the anion is sulfite (SO_3^{2-}), the correct name for MgSO_3 is magnesium sulfite.
5. Verify that the charges balance to form a neutral compound: Mg^{2+} and SO_3^{2-} combine in a 1:1 ratio, confirming the formula MgSO_3 corresponds to magnesium sulfite.