Na2S2O3 (aq) + 4 Cl2 (g) + 5 H2O (l) 2 NaHSO4 (aq) + 8 HCl (aq)

This is an oxidation-reduction (redox) reaction:

2 SII - 8 e- 2 SVI (oxidation)

8 Cl0 + 8 e- 8 Cl-I (reduction)

Na2S2O3 is a reducing agent, Cl2 is an oxidizing agent.

Reactants:

  • Na2S2O3
    • Names: Sodium thiosulfate source: wikipedia, accessed on: 2019-09-28source: wikidata, accessed on: 2019-09-02source: ICSC, accessed on: 2019-09-04, Sodium hyposulfite source: wikipedia, accessed on: 2019-09-28source: wikidata, accessed on: 2019-09-02, Hyposulphite of soda source: wikipedia, accessed on: 2019-09-28
    • Appearance: White crystals source: wikipedia, accessed on: 2019-09-28; Colourless crystals source: ICSC, accessed on: 2019-09-04
  • Cl2
    • Names: Chlorine source: ICSC, accessed on: 2019-09-04source: NIOSH NPG, accessed on: 2019-09-02, Molecular chlorine source: NIOSH NPG, accessed on: 2019-09-02
    • Appearance: Greenish-yellow compressed liquefied gas with pungent odour source: ICSC, accessed on: 2019-09-04; Greenish-yellow gas with a pungent, irritating odor. [Note: 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:

  • NaHSO4Sodium hydrogen sulfate source: wikipedia, accessed on: 2019-09-27source: wikidata, accessed on: 2019-09-02
    • Other names: Sodium bisulfate source: wikipedia, accessed on: 2019-09-27source: wikidata, accessed on: 2019-09-02, Sodium acid sulfate source: wikipedia, accessed on: 2019-09-27, Bisulfate of soda source: wikipedia, accessed on: 2019-09-27
    • Appearance: White solid source: wikipedia, accessed on: 2019-09-27
  • 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