2 IO3- + 5 SO32- + 2 H+ → I2 + 5 SO42- + H2O

This is an oxidation-reduction (redox) reaction:

5 SIV - 10 e- → 5 SVI (oxidation)

2 IV + 10 e- → 2 I0 (reduction)

SO32- is a reducing agent, IO3- is an oxidizing agent.

Reactants:

  • IO3-
  • SO32-
  • H+

Products:

  • I2
    • Names: Iodine source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02, Jod source: ICSC, accessed: 2019-09-04, Iode source: ICSC, accessed: 2019-09-04
    • Appearance: Bluish black or dark purple crystals with pungent odour source: ICSC, accessed: 2019-09-04; Violet solid with a sharp, characteristic odor. source: NIOSH NPG, accessed: 2019-09-02
  • SO42- – Sulfate source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-07
    • Other names: Sulfate ion source: wikidata, accessed: 2019-09-07, Sulphate ion source: wikidata, accessed: 2019-09-07, Sulphate source: wikidata, accessed: 2019-09-07
  • 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