H2O + I2 + H3PO2 → 2 HI + H3PO3

This is an oxidation-reduction (redox) reaction:

PI - 2 e- → PIII (oxidation)

2 I0 + 2 e- → 2 I-I (reduction)

H3PO2 is a reducing agent, I2 is an oxidizing agent.

Reactants:

  • H2O – Water, oxidane source: wikipedia, accessed: 2019-09-27
    • Other names: Water (H2O) source: wikipedia, accessed: 2019-09-27, Hydrogen hydroxide (HH or HOH) source: wikipedia, accessed: 2019-09-27, Hydrogen oxide source: wikipedia, accessed: 2019-09-27
    • Appearance: White crystalline solid, almost colorless liquid with a hint of blue, colorless gas source: wikipedia, accessed: 2019-09-27
  • I2
    • Names: Iodine source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02, Jod source: ICSC, accessed: 2019-09-04, Iode source: ICSC, accessed: 2019-09-04
    • Appearance: Bluish black or dark purple crystals with pungent odour source: ICSC, accessed: 2019-09-04; Violet solid with a sharp, characteristic odor. source: NIOSH NPG, accessed: 2019-09-02
  • H3PO2 – Phosphinic acid source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02
    • Other names: Hypophosphorous acid source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02, Hydroxy(oxo)-λ5-phosphane source: wikipedia, accessed: 2019-09-27
    • Appearance: Colorless, deliquescent crystals or oily liquid source: wikipedia, accessed: 2019-09-27

Products:

  • HI – Iodane source: wikipedia, accessed: 2019-09-27
    • Other names: Hydroiodic acid source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02, Hydrogen iodide source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04, Hydronium iodide source: wikipedia, accessed: 2019-09-27
    • Appearance: Colorless liquid source: wikipedia, accessed: 2019-09-27; Colorless gas source: wikipedia, accessed: 2019-09-27; Colourless compressed liquefied gas with pungent odour source: ICSC, accessed: 2019-09-04
  • H3PO3 – Phosphonic acid source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-04
    • Other names: Phosphorous acid source: wikipedia, accessed: 2019-09-27, Dihydroxyphosphine oxide source: wikipedia, accessed: 2019-09-27
    • Appearance: White solid | deliquescent source: wikipedia, accessed: 2019-09-27