2 Ca3(PO4)2 + 5 C + 6 SiO2 → P4 + 5 CO2 + 6 CaSiO3

This is an oxidation-reduction (redox) reaction:

4 PV + 20 e- → 4 P0 (reduction)

5 C0 - 20 e- → 5 CIV (oxidation)

Ca3(PO4)2 is an oxidizing agent, C is a reducing agent.

Reactants:

  • Ca3(PO4)2 – Tricalcium bis(phosphate) source: wikipedia, accessed: 2019-09-28
    • Other names: Tricalcium phosphate source: wikipedia, accessed: 2019-09-28source: wikidata, accessed: 2019-09-02, Tribasic calcium phosphate source: wikipedia, accessed: 2019-09-28source: wikidata, accessed: 2019-09-02, Bone phosphate of lime source: wikidata, accessed: 2019-09-02
    • Appearance: White amorphous powder source: wikipedia, accessed: 2019-09-28
  • C
    • Names: Carbon black source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02, Acetylene black source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02, Channel black source: wikidata, accessed: 2019-09-02source: NIOSH NPG, accessed: 2019-09-02
    • Appearance: Odourless black pellets or extremely fine powder source: ICSC, accessed: 2019-09-04; Black, odorless solid. source: NIOSH NPG, accessed: 2019-09-02
  • SiO2

    Products:

    • P4
    • 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
    • CaSiO3 – Calcium silicate source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: NIOSH NPG, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04, Dicalcium silicate source: wikipedia, accessed: 2019-09-27
      • Other names: Belite source: wikipedia, accessed: 2019-09-27, Silicic acid, calcium salt (non-fibrous, <1% crystalline silica) source: ICSC, accessed: 2019-09-04, Calcium hydrosilicate source: wikidata, accessed: 2019-09-02source: NIOSH NPG, accessed: 2019-09-02
      • Appearance: White crystals source: wikipedia, accessed: 2019-09-27; White powder source: ICSC, accessed: 2019-09-04; White or cream-colored, free-flowing powder. [Note: The commercial product is prepared from diatomaceous earth & lime.] source: NIOSH NPG, accessed: 2019-09-02