MnSO₄ + KBrO₃ + KOH = K₂MnO₄ + KBr + K₂SO₄ + H₂O
3 | Mn²⁺ - 4e + 8OH⁻ = MnO₄²⁻ + 4H₂O
2 | BrO₃⁻ + 6e + 3H₂O = Br⁻ + 6OH⁻
__________________________________
3Mn²⁺ + 12OH⁻ + 2BrO₃⁻ = 3MnO₄²⁻ + 6H₂O + 2Br⁻
3MnSO₄ + 2KBrO₃ + 12KOH = 3K₂MnO₄ + 2KBr + 3K₂SO₄ + 6H₂O