10NaH2PO2 + 4NaMnO4 + 3Na2SO4 + H2SO4 → 10Na2HPO3 + 4MnSO4 + 6H2O
Sodium hypophosphite react with sodium permanganate, sodium sulfate and sulfuric acid to produce disodium hydrogen phosphite, manganese(II) sulfate and water. Sulfuric acid - diluted solution.