Sulfur Dioxide Reduction of Dichromate

Cr2O72− + 3SO2 + 2H+ → 2Cr3+ + 3SO42− + H2O

Übersicht

Sulfur dioxide reduces orange dichromate to green chromium(III) while being oxidized to sulfate. This reaction changes the solution color from orange to green and is used as a test for SO₂ gas. Cr(VI) gains 3 electrons per atom while S(IV) loses 2 electrons per atom.

Teilnehmer

Rolle Substanz Koeffizient Zustand
Reaktant Sulfur Dioxide SO₂ 3 (g)
Produkt Water H₂O 1 (l)

Alltägliches Beispiel

Dichromate-impregnated paper is used as a sensitive test for sulfur dioxide gas, turning from orange to green in its presence.

Industrielle Bedeutung

This reaction is relevant to flue gas monitoring, environmental SO₂ detection, and understanding chromium redox chemistry in industrial processes.

Eigenschaften

Typ
Redox
Reversibel
Nein
Energie
Exotherm
ΔH
-850,0 kJ/mol

Verwandte Reaktionen

Iron(II) to Iron(III) Oxidation by Oxygen Bleaching with Sodium Hypochlorite Copper Reduction of Silver Ion Aqua Regia Dissolving Gold Cerium(IV) Reduction by Iron(II) Copper Oxidation by Nitric Acid Hypochlorite Oxidation of Hydrogen Peroxide Hydrogen Peroxide as Oxidizing Agent (Acidic) Hydrogen Peroxide Disproportionation Displacement of Hydrogen from Acid by Magnesium

Frequently Asked Questions

What is the equation for Sulfur Dioxide Reduction of Dichromate?
The balanced equation is: Cr₂O₇²⁻ + 3SO₂ + 2H⁺ → 2Cr³⁺ + 3SO₄²⁻ + H₂O.
What type of reaction is Sulfur Dioxide Reduction of Dichromate?
Sulfur Dioxide Reduction of Dichromate is a redox reaction.
Is Sulfur Dioxide Reduction of Dichromate exothermic or endothermic?
Sulfur Dioxide Reduction of Dichromate is exothermic (releases energy). The enthalpy change (ΔH) is -850.0 kJ/mol.