4 CuS + 5 O2 → 2 Cu2O + 4 SO2

This is an oxidation-reduction (redox) reaction:

4 CuII + 4 e- → 4 CuI (reduction)

4 S-II - 24 e- → 4 SIV (oxidation)

10 O0 + 20 e- → 10 O-II (reduction)

CuS is an oxidizing agent, CuS is a reducing agent, O2 is an oxidizing agent.

Reactants:

  • CuS – Copper sulfide source: wikipedia, accessed: 2019-09-27
    • Other names: Copper monosulfide source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02, Covellite source: wikipedia, accessed: 2019-09-27, Copper(II) sulfide source: wikipedia, accessed: 2019-09-27, Cupric sulfide source: wikipedia, accessed: 2019-09-27
    • Appearance: Black powder or lumps source: wikipedia, accessed: 2019-09-27
  • O2
    • Names: Dioxygen source: wikidata, accessed: 2019-09-07, Oxygen source: ICSC, accessed: 2019-09-04source: wikidata, accessed: 2019-09-07, Oxygen (liquefied) source: ICSC, accessed: 2019-09-04
    • Appearance: Odourless compressed gas source: ICSC, accessed: 2019-09-04; Liquefied gas. colourless-to-blue extremely cold liquid source: ICSC, accessed: 2019-09-04

Products:

  • Cu2O – Copper(I) oxide source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02
    • Other names: Cuprous oxide source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04, Dicopper oxide source: wikipedia, accessed: 2019-09-27source: ICSC, accessed: 2019-09-04, Cuprite source: wikipedia, accessed: 2019-09-27
    • Appearance: Brownish-red solid source: wikipedia, accessed: 2019-09-27; Yellow, red or brown crystalline powder source: ICSC, accessed: 2019-09-04
  • 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