3 K2S + 4 KBrO3 → 3 K2SO4 + 4 KBr

This is an oxidation-reduction (redox) reaction:

4 BrV + 24 e- → 4 Br-I (reduction)

3 S-II - 24 e- → 3 SVI (oxidation)

KBrO3 is an oxidizing agent, K2S is a reducing agent.

Reactants:

  • K2S – Potassium sulfide source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04
    • Other names: Dipotassium monosulfide source: wikipedia, accessed: 2019-09-27source: ICSC, accessed: 2019-09-04, Dipotassium sulfide source: wikipedia, accessed: 2019-09-27source: ICSC, accessed: 2019-09-04, Potassium monosulfide source: wikipedia, accessed: 2019-09-27source: ICSC, accessed: 2019-09-04
    • Appearance: Pure: colourless | impure: yellow-brown source: wikipedia, accessed: 2019-09-27; Hygroscopic white crystals with characteristic odour. turns red or brown on exposure to air source: ICSC, accessed: 2019-09-04
  • KBrO3 – Potassium bromate source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04
    • Other names: Potassium bromate(V) source: wikipedia, accessed: 2019-09-27, Bromic acid source: wikipedia, accessed: 2019-09-27, Potassium salt source: wikipedia, accessed: 2019-09-27
    • Appearance: White crystalline powder source: wikipedia, accessed: 2019-09-27; White crystals or powder source: ICSC, accessed: 2019-09-04

Products:

  • K2SO4
    • Names: Potassium sulfate source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04, Potassium sulphate source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02, Dipotassium sulfate source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04
    • Appearance: White solid source: wikipedia, accessed: 2019-09-27; Colourless-to-white crystals source: ICSC, accessed: 2019-09-04
  • KBr
    • Names: Potassium bromide source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02, KBr source: wikidata, accessed: 2019-09-02, Kaliumbromid source: wikidata, accessed: 2019-09-02
    • Appearance: White solid source: wikipedia, accessed: 2019-09-27