CrCl2 (aq) + 8 KOH (aq) + 2 Br2 (aq) → 4 KBr (aq) + 2 KCl (aq) + K2CrO4 (aq) + 4 H2O (l)

This is an oxidation-reduction (redox) reaction:

4 Br0 + 4 e- → 4 Br-I (reduction)

CrII - 4 e- → CrVI (oxidation)

Br2 is an oxidizing agent, CrCl2 is a reducing agent.

Reactants:

  • CrCl2 – Chromium(II) chloride source: wikipedia, accessed: 2019-09-27source: ICSC, accessed: 2019-09-04
    • Other names: Chromous chloride source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04, Chromium dichloride source: ICSC, accessed: 2019-09-04
    • Appearance: White to grey/green powder (anhydrous), very hygroscopic source: wikipedia, accessed: 2019-09-27; Very hygroscopic solid in various forms source: ICSC, accessed: 2019-09-04
  • KOH – Potassium hydroxide source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02
    • Other names: Caustic potash source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02, Lye source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02, Potash lye source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02
    • Appearance: White solid, deliquescent source: wikipedia, accessed: 2019-09-27; White hygroscopic solid in various forms source: ICSC, accessed: 2019-09-04; Odorless, white or slightly yellow lumps, rods, flakes, sticks, or pellets. [Note: May be used as an aqueous solution.] source: NIOSH NPG, accessed: 2019-09-02
  • 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

Products:

  • 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
  • KCl
    • Names: Potassium chloride source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04, Sylvite source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02, Muriate of potash source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02
    • Appearance: White crystalline solid source: wikipedia, accessed: 2019-09-27; Colourless hygroscopic crystals source: ICSC, accessed: 2019-09-04
  • K2CrO4 – Potassium chromate source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04
    • Other names: Chromic acid source: wikipedia, accessed: 2019-09-27, (K2CrO4) source: wikipedia, accessed: 2019-09-27, Dipotassium salt source: wikipedia, accessed: 2019-09-27
    • Appearance: Yellow powder source: wikipedia, accessed: 2019-09-27; Yellow crystals source: ICSC, accessed: 2019-09-04
  • 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