Sulfur Dioxide Reduction of Dichromate

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

Descripción general

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.

Participantes

Rol	Sustancia	Coeficiente	Estado
Reactivo	Sulfur Dioxide SO₂	3	(g)
Producto	Water H₂O	1	(l)

Ejemplo cotidiano

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

Importancia industrial

Aplicado en la reducción de Cr(VI) tóxico a Cr(III) en el tratamiento de efluentes de galvanoplastia.

Propiedades

Tipo: Redox
Reversible: No
Energía: Exotérmico
ΔH: -850,0 kJ/mol

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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.