2 As2S3 + 28 NaNO3 + 9 Na2CO3 + 3 H2O → 4 Na3AsO4 + 6 NaHSO4 + 28 NaNO2 + 9 CO2

This is an oxidation-reduction (redox) reaction:

4 AsIII - 8 e- → 4 AsV (oxidation)

6 S-II - 48 e- → 6 SVI (oxidation)

28 NV + 56 e- → 28 NIII (reduction)

As2S3 is a reducing agent, As2S3 is a reducing agent, NaNO3 is an oxidizing agent.

Reactants:

  • As2S3 – Arsenic trisulfide source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02
    • Other names: Arsenic(III) sulfide source: wikipedia, accessed: 2019-09-27
    • Appearance: Orange crystals source: wikipedia, accessed: 2019-09-27
  • NaNO3 – Sodium nitrate source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04
    • Other names: Peru saltpeter source: wikipedia, accessed: 2019-09-27, Soda niter source: wikipedia, accessed: 2019-09-27, Cubic niter source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02
    • Appearance: White powder or colorless crystals source: wikipedia, accessed: 2019-09-27; Colourless hygroscopic crystals source: ICSC, accessed: 2019-09-04
  • Na2CO3 – Sodium carbonate source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02
    • Other names: Soda ash source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04, Washing soda source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02, Soda crystals source: wikipedia, accessed: 2019-09-27
    • Appearance: White solid, hygroscopic source: wikipedia, accessed: 2019-09-27; White hygroscopic powder 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

Products:

  • Na3AsO4
  • NaHSO4 – Sodium hydrogen sulfate source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02
    • Other names: Sodium bisulfate source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02, Sodium acid sulfate source: wikipedia, accessed: 2019-09-27, Bisulfate of soda source: wikipedia, accessed: 2019-09-27
    • Appearance: White solid source: wikipedia, accessed: 2019-09-27
  • NaNO2
    • Names: Sodium nitrite source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04, 7632-00-0 source: wikidata, accessed: 2019-09-02, E250 source: wikidata, accessed: 2019-09-02
    • Appearance: White or slightly yellowish solid source: wikipedia, accessed: 2019-09-27; Hygroscopic white-to-yellow solid in various forms source: ICSC, accessed: 2019-09-04
  • CO2
    • Names: Carbon dioxide source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02, {{plainlist| source: wikipedia, accessed: 2019-09-27, CO2 source: wikidata, accessed: 2019-09-02
    • Appearance: Colorless gas source: wikipedia, accessed: 2019-09-27; Odourless colourless compressed liquefied gas source: ICSC, accessed: 2019-09-04; Colorless, odorless gas. [Note: Shipped as a liquefied compressed gas. Solid form is utilized as dry ice.] source: NIOSH NPG, accessed: 2019-09-02