SO2 + Fe2(SO4)3 + 2 H2O 2 FeSO4 + 2 H2SO4

This is an oxidation-reduction (redox) reaction:

SIV - 2 e- SVI (oxidation)

2 FeIII + 2 e- 2 FeII (reduction)

SO2 is a reducing agent, Fe2(SO4)3 is an oxidizing agent.

Reactants:

  • SO2Sulfur dioxide source: wikipedia, accessed on: 2019-09-28source: wikidata, accessed on: 2019-09-02source: NIOSH NPG, accessed on: 2019-09-02
    • Other names: Sulfurous anhydride source: wikipedia, accessed on: 2019-09-28source: wikidata, accessed on: 2019-09-02source: ICSC, accessed on: 2019-09-04, Sulphur dioxide source: ICSC, accessed on: 2019-09-04source: wikidata, accessed on: 2019-09-02, Sulfurous acid anhydride source: wikidata, accessed on: 2019-09-02source: NIOSH NPG, accessed on: 2019-09-02
    • Appearance: Colorless gas source: wikipedia, accessed on: 2019-09-28; Colourless gas or compressed liquefied gas with pungent odour source: ICSC, accessed on: 2019-09-04; Colorless gas with a characteristic, irritating, pungent odor. [Note: A liquid below 14°F. Shipped as a liquefied compressed gas.] source: NIOSH NPG, accessed on: 2019-09-02
  • Fe2(SO4)3Iron(III) sulfate source: wikipedia, accessed on: 2019-09-27source: wikidata, accessed on: 2019-09-02
    • Other names: Ferric sulfate source: wikipedia, accessed on: 2019-09-27source: wikidata, accessed on: 2019-09-02, Sulfuric acid source: wikipedia, accessed on: 2019-09-27, Iron(3+) salt (3:2) source: wikipedia, accessed on: 2019-09-27
    • Appearance: Grayish-white crystals source: wikipedia, accessed on: 2019-09-27
  • H2OWater, oxidane source: wikipedia, accessed on: 2019-09-27
    • Other names: Water (H2O) source: wikipedia, accessed on: 2019-09-27, Hydrogen hydroxide (HH or HOH) source: wikipedia, accessed on: 2019-09-27, Hydrogen oxide source: wikipedia, accessed on: 2019-09-27
    • Appearance: White crystalline solid, almost colorless liquid with a hint of blue, colorless gas source: wikipedia, accessed on: 2019-09-27

Products:

  • FeSO4Iron(II) sulphate source: wikipedia, accessed on: 2019-09-27
    • Other names: Iron(II) sulfate source: wikipedia, accessed on: 2019-09-27source: wikidata, accessed on: 2019-09-02, Ferrous sulfate source: wikipedia, accessed on: 2019-09-27, Green vitriol source: wikipedia, accessed on: 2019-09-27
    • Appearance: White crystals (anhydrous) | White-yellow crystals (monohydrate) | Blue-green crystals (heptahydrate) source: wikipedia, accessed on: 2019-09-27
  • H2SO4Sulfuric acid source: wikipedia, accessed on: 2019-09-27source: wikidata, accessed on: 2019-09-07source: NIOSH NPG, accessed on: 2019-09-02
    • Other names: Oil of vitriol source: wikipedia, accessed on: 2019-09-27source: wikidata, accessed on: 2019-09-07source: ICSC, accessed on: 2019-09-04source: NIOSH NPG, accessed on: 2019-09-02, Sulfuric acid, concentrated (> 51% and < 100%) source: ICSC, accessed on: 2019-09-04, H2SO4 source: wikidata, accessed on: 2019-09-07
    • Appearance: Clear, colorless liquid source: wikipedia, accessed on: 2019-09-27; Odourless colourless oily hygroscopic liquid source: ICSC, accessed on: 2019-09-04; Colorless to dark-brown, oily, odorless liquid. [Note: Pure compound is a solid below 51°F. Often used in an aqueous solution.] source: NIOSH NPG, accessed on: 2019-09-02