What is the formula of magnesium sulfite

What is the formula of magnesium sulfite? A) MgSO4 B) MgSO3 C) MgS D) MgSO

The Correct Answer and Explanation is:

The correct formula for magnesium sulfite is MgSO3 (option B).

Explanation:

Magnesium sulfite is a chemical compound composed of magnesium ions (Mg²⁺) and sulfite ions (SO₃²⁻). The sulfite ion is derived from sulfurous acid (H₂SO₃) and consists of one sulfur atom bonded to three oxygen atoms, with a charge of 2-.

To form a neutral compound, the charges of the magnesium ions and sulfite ions must balance. Magnesium ions have a +2 charge, and sulfite ions have a -2 charge. Therefore, one magnesium ion combines with one sulfite ion to form the neutral compound magnesium sulfite. This results in the formula MgSO3.

Breakdown of the options:

  • A) MgSO4: This is the formula for magnesium sulfate, not magnesium sulfite. Sulfate (SO₄²⁻) has one more oxygen atom than sulfite (SO₃²⁻).
  • B) MgSO3: This is the correct formula for magnesium sulfite, where the charges of the magnesium ion and sulfite ion are balanced.
  • C) MgS: This is the formula for magnesium sulfide, a different compound formed when magnesium reacts with sulfur (S), not sulfite.
  • D) MgSO: This is not a valid formula for any known compound. Sulfite requires three oxygen atoms (SO₃²⁻), not just one.

Thus, the correct formula for magnesium sulfite is MgSO3.

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