3 SO2 (aq) + 6 Na2CO3 (aq) + 2 AuCl3 (aq) → 6 CO2 (g) + 6 NaCl (aq) + 3 Na2SO4 (aq) + 2 Au (s)

This is an oxidation-reduction (redox) reaction:

3 SIV - 6 e- → 3 SVI (oxidation)

2 AuIII + 6 e- → 2 Au0 (reduction)

SO2 is a reducing agent, AuCl3 is an oxidizing agent.

This is a precipitation reaction: Au is the formed precipitate.

This is a gas evolution reaction, CO2 is the formed gas.

Reactants:

  • SO2 – Sulfur dioxide source: wikipedia, accessed: 2019-09-28source: wikidata, accessed: 2019-09-02source: NIOSH NPG, accessed: 2019-09-02
    • Other names: Sulfurous anhydride source: wikipedia, accessed: 2019-09-28source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04, Sulphur dioxide source: ICSC, accessed: 2019-09-04source: wikidata, accessed: 2019-09-02, Sulfurous acid anhydride source: wikidata, accessed: 2019-09-02source: NIOSH NPG, accessed: 2019-09-02
    • Appearance: Colorless gas source: wikipedia, accessed: 2019-09-28; Colourless gas or compressed liquefied gas with pungent odour source: ICSC, accessed: 2019-09-04; Colorless gas with a characteristic, irritating, pungent odor. [Note: A liquid below 14°F. Shipped as a liquefied compressed gas.] source: NIOSH NPG, accessed: 2019-09-02
  • 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
  • AuCl3 – Gold(III) trichloride source: wikipedia, accessed: 2019-09-27
    • Other names: Gold(III) chloride source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02, Auric chloride source: wikipedia, accessed: 2019-09-27, Gold trichloride source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02
    • Appearance: Red crystals (anhydrous); golden, yellow crystals (monohydrate) source: wikipedia, accessed: 2019-09-27

Products:

  • 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
  • NaCl – Sodium chloride source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02
    • Other names: {{unbulleted list source: wikipedia, accessed: 2019-09-27, Salt source: wikidata, accessed: 2019-09-02, Table salt source: wikidata, accessed: 2019-09-02
    • Appearance: Colorless cubic crystals source: wikipedia, accessed: 2019-09-27
  • Na2SO4
    • Names: Sodium sulfate source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04, Sodium sulphate source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02, Sulfate of sodium source: wikipedia, accessed: 2019-09-27
    • Appearance: White crystalline solid | hygroscopic source: wikipedia, accessed: 2019-09-27; White hygroscopic solid in various forms source: ICSC, accessed: 2019-09-04
  • Au
    • Names: Gold source: wikidata, accessed: 2019-09-07, Au source: wikidata, accessed: 2019-09-07, Element 79 source: wikidata, accessed: 2019-09-07, Aurum source: wikidata, accessed: 2019-09-07