3 Mg + Cr2O3 → 2 Cr + 3 MgO

This is an oxidation-reduction (redox) reaction:

3 Mg0 - 6 e- → 3 MgII (oxidation)

2 CrIII + 6 e- → 2 Cr0 (reduction)

Mg is a reducing agent, Cr2O3 is an oxidizing agent.

Reactants:

  • Mg
    • Names: Magnesium source: wikidata, accessed: 2019-09-07, Magnesium (powder) source: ICSC, accessed: 2019-09-04, Magnesium (pellets) source: ICSC, accessed: 2019-09-04
    • Appearance: Grey powder source: ICSC, accessed: 2019-09-04; Silvery-white metallic solid in various forms source: ICSC, accessed: 2019-09-04
  • Cr2O3
    • Names: Chromium(III) oxide source: wikipedia, accessed: 2019-09-27, Chromium sesquioxide source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02, Chromia source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02
    • Appearance: Light to dark green, fine crystals source: wikipedia, accessed: 2019-09-27; Light-to-dark-green powder source: ICSC, accessed: 2019-09-04

Products:

  • Cr
    • Names: Chromium source: wikidata, accessed: 2019-09-07source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02, Chromium metal source: NIOSH NPG, accessed: 2019-09-02, Cr source: wikidata, accessed: 2019-09-07
    • Appearance: Grey powder source: ICSC, accessed: 2019-09-04; Blue-white to steel-gray, lustrous, brittle, hard, odorless solid. source: NIOSH NPG, accessed: 2019-09-02
  • MgO – Magnesium oxide source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04
    • Other names: Magnesia source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04, Periclase source: wikipedia, accessed: 2019-09-27, Magnesium oxide fume source: NIOSH NPG, accessed: 2019-09-02
    • Appearance: White powder source: wikipedia, accessed: 2019-09-27; Hygroscopic fine white powder source: ICSC, accessed: 2019-09-04; Finely divided white particulate dispersed in air. [Note: Exposure may occur when magnesium is burned, thermally cut, or welded upon.] source: NIOSH NPG, accessed: 2019-09-02