Which of the following is the correct chemical formula for magnesium fluoride?

• A. Mg2F
• B. Mg2F2
• C. MgF2
• D. MgF

Answer: (C)

Verified step by step guidance

1. Identify the charges of the ions involved: magnesium typically forms a Mg^{2+} ion, and fluoride forms an F^{-} ion.
2. Determine the ratio of ions needed to balance the overall charge to zero. Since Mg^{2+} has a +2 charge and F^{-} has a -1 charge, two fluoride ions are needed to balance one magnesium ion.
3. Write the chemical formula by combining one Mg^{2+} ion with two F^{-} ions, resulting in MgF_{2}.
4. Check that the total positive charge (+2 from Mg^{2+}) balances the total negative charge (2 × -1 from two F^{-} ions), confirming the compound is electrically neutral.
5. Conclude that the correct chemical formula for magnesium fluoride is MgF_{2}.