Give chemical equation of reaction when pyrolusite ore is fused with KOH in presence of air.
Why is hydrochloric acid not used to acidify a permanganate solution in volumetric estimation of Fe2+ or C2O42–?
Write an ionic equation representing the oxidising property of acidified potassium permanganate solution.
Sulfur dioxide gas turns acidified potassium dichromate solution from orange to green reduced chromium +4 to +3.
K2Cr2O7 + 2H2SO4 + 3SO2 → 2Cr2(SO4)3 + K2SO4 + H2O