5 SO3 + 2 P → P2O5 + 5 SO2

This is an oxidation-reduction (redox) reaction:

2 P0 - 10 e- → 2 PV (oxidation)

5 SVI + 10 e- → 5 SIV (reduction)

P is a reducing agent, SO3 is an oxidizing agent.

Reactants:

  • SO3 – Sulfur trioxide source: wikipedia, accessed: 2019-09-28source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04, Sulfonylideneoxidane source: wikipedia, accessed: 2019-09-28
    • Other names: Sulfuric anhydride source: wikipedia, accessed: 2019-09-28, Sulfur(VI) oxide source: wikipedia, accessed: 2019-09-28, SO3 source: wikidata, accessed: 2019-09-02
    • Appearance: Colorless to white crystalline solid which will fume in air.{{ source: wikipedia, accessed: 2019-09-28; Fuming hygroscopic colourless liquid or colourless-to-white crystals source: ICSC, accessed: 2019-09-04
  • P

    Products:

    • P2O5
      • Names: Phosphorus pentoxide source: wikipedia, accessed: 2019-09-27source: ICSC, accessed: 2019-09-04, Diphosphorus pentoxide source: wikipedia, accessed: 2019-09-27source: ICSC, accessed: 2019-09-04, Phosphorus(V) oxide source: wikipedia, accessed: 2019-09-27
      • Appearance: White powder | very deliquescent | odorless source: wikipedia, accessed: 2019-09-27; Hygroscopic white crystals or 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