HClO4 (l) + 4 SO2 (aq) + 4 H2O (l) 4 H2SO4 (aq) + HCl (aq)

This is an oxidation-reduction (redox) reaction:

4 SIV - 8 e- 4 SVI (oxidation)

ClVII + 8 e- Cl-I (reduction)

SO2 is a reducing agent, HClO4 is an oxidizing agent.

Reactants:

  • HClO4Chloric(VII) acid source: wikipedia, accessed on: 2019-09-27
    • Other names: Perchloric acid source: wikipedia, accessed on: 2019-09-27source: wikidata, accessed on: 2019-09-02, Hyperchloric acid source: wikipedia, accessed on: 2019-09-27, Perchloric acid (72% solution) source: ICSC, accessed on: 2019-09-04, Hydronium perchlorate source: ICSC, accessed on: 2019-09-04
    • Appearance: Colorless liquid source: wikipedia, accessed on: 2019-09-27; Colourless liquid with pungent odour source: ICSC, accessed on: 2019-09-04
  • 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
  • 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:

  • 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
  • HClChlorane source: wikipedia, accessed on: 2019-09-27, Hydrogen chloride source: wikipedia, accessed on: 2019-09-27source: wikidata, accessed on: 2019-09-02source: ICSC, accessed on: 2019-09-04source: NIOSH NPG, accessed on: 2019-09-02
    • Other names: Hydrochloric acid source: wikipedia, accessed on: 2019-09-27source: NIOSH NPG, accessed on: 2019-09-02, Hydrochloric acid gas source: wikipedia, accessed on: 2019-09-27, HCl source: wikidata, accessed on: 2019-09-02
    • Appearance: Colorless, transparent liquid, fumes in air if concentrated source: wikipedia, accessed on: 2019-09-27; Colorless gas source: wikipedia, accessed on: 2019-09-27; Colourless compressed liquefied gas with pungent odour source: ICSC, accessed on: 2019-09-04; Colorless to slightly yellow gas with a pungent, irritating odor. [Note: Shipped as a liquefied compressed gas.] source: NIOSH NPG, accessed on: 2019-09-02