H2O + Br2 + H2SO3 → H2SO4 + 2 HBr

This is an oxidation-reduction (redox) reaction:

2 Br0 + 2 e- → 2 Br-I (reduction)

SIV - 2 e- → SVI (oxidation)

Br2 is an oxidizing agent, H2SO3 is a reducing agent.

Reactants:

  • H2O – Water, oxidane source: wikipedia, accessed: 2019-09-27
    • Other names: Water (H2O) source: wikipedia, accessed: 2019-09-27, Hydrogen hydroxide (HH or HOH) source: wikipedia, accessed: 2019-09-27, Hydrogen oxide source: wikipedia, accessed: 2019-09-27
    • Appearance: White crystalline solid, almost colorless liquid with a hint of blue, colorless gas source: wikipedia, accessed: 2019-09-27
  • Br2
    • Names: Bromine source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02, Molecular bromine source: NIOSH NPG, accessed: 2019-09-02
    • Appearance: Fuming red-to-brown liquid with pungent odour source: ICSC, accessed: 2019-09-04; Dark reddish-brown, fuming liquid with suffocating, irritating fumes. source: NIOSH NPG, accessed: 2019-09-02
  • H2SO3 – Sulfurous acid source: wikipedia, accessed: 2019-09-28source: wikidata, accessed: 2019-09-02
    • Other names: S(O)(OH)2 source: wikidata, accessed: 2019-09-02, Sulphurous acid source: wikidata, accessed: 2019-09-02

Products:

  • H2SO4 – Sulfuric acid source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-07source: NIOSH NPG, accessed: 2019-09-02
    • Other names: Oil of vitriol source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-07source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02, Sulfuric acid, concentrated (> 51% and < 100%) source: ICSC, accessed: 2019-09-04, H2SO4 source: wikidata, accessed: 2019-09-07
    • Appearance: Clear, colorless liquid source: wikipedia, accessed: 2019-09-27; Odourless colourless oily hygroscopic liquid source: ICSC, accessed: 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: 2019-09-02
  • HBr – Hydrogen bromide source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02, Bromane source: wikipedia, accessed: 2019-09-27source: wikipedia, accessed: 2019-09-27
    • Other names: Hydrobromic acid source: wikipedia, accessed: 2019-09-27source: ICSC, accessed: 2019-09-04, Hydronium bromide source: wikipedia, accessed: 2019-09-27, HBr source: wikidata, accessed: 2019-09-02
    • Appearance: Colorless gas source: wikipedia, accessed: 2019-09-27; Colorless/faint yellow liquid source: wikipedia, accessed: 2019-09-27; Colourless compressed liquefied gas with pungent odour source: ICSC, accessed: 2019-09-04; Colorless gas with a sharp, irritating odor. [Note: Shipped as a liquefied compressed gas. Often used in an aqueous solution.] source: NIOSH NPG, accessed: 2019-09-02