2 NaOH + H2SO3 → 2 H2O + Na2SO3

This is an acid-base reaction (neutralization): NaOH is a base, H2SO3 is an acid.

Reactants:

  • NaOH
    • Names: Sodium hydroxide source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02, Caustic soda source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02, Lye source: wikidata, accessed: 2019-09-02
    • Appearance: White, waxy, opaque crystals source: wikipedia, accessed: 2019-09-27; White hygroscopic solid in various forms source: ICSC, accessed: 2019-09-04; Colorless to white, odorless solid (flakes, beads, granular form). source: NIOSH NPG, accessed: 2019-09-02
  • H2SO3 – Sulfurous acid source: wikipedia, accessed: 2019-09-28source: wikidata, accessed: 2019-09-02
    • Other names: S(O)(OH)2 source: wikidata, accessed: 2019-09-02, Sulphurous acid source: wikidata, accessed: 2019-09-02

Products:

  • 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
  • Na2SO3 – Sodium sulfite source: wikipedia, accessed: 2019-09-28source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04
    • Other names: Sodium sulphite source: wikipedia, accessed: 2019-09-28source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04, Hypo clear (photography) source: wikipedia, accessed: 2019-09-28, E221 source: wikipedia, accessed: 2019-09-28
    • Appearance: White solid source: wikipedia, accessed: 2019-09-28; White crystals or powder source: ICSC, accessed: 2019-09-04