2 Na2S + 4 Ag + 2 H2O + O2 4 NaOH + 2 Ag2S

This is an oxidation-reduction (redox) reaction:

4 Ag0 - 4 e- 4 AgI (oxidation)

2 O0 + 4 e- 2 O-II (reduction)

Ag is a reducing agent, O2 is an oxidizing agent.

Reactants:

  • Na2S
    • Names: Sodium sulfide source: wikipedia, accessed: 2019-09-28source: wikidata, accessed: 2019-09-02, Disodium sulfide source: wikipedia, accessed: 2019-09-28source: wikidata, accessed: 2019-09-02, Sodium sulfide (anhydrous) source: ICSC, accessed: 2019-09-04
    • Appearance: Colorless, hygroscopic solid source: wikipedia, accessed: 2019-09-28; White-to-yellow hygroscopic crystals with characteristic odour source: ICSC, accessed: 2019-09-04
  • Ag
    • Names: Silver source: wikidata, accessed: 2019-09-07source: ICSC, accessed: 2019-09-04, Ag source: wikidata, accessed: 2019-09-07, Element 47 source: wikidata, accessed: 2019-09-07
    • Appearance: White metal. turns dark on exposure to ozone, hydrogen sulfide or sulfur source: ICSC, accessed: 2019-09-04
  • H2OWater, 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
  • O2
    • Names: Dioxygen source: wikidata, accessed: 2019-09-07, Oxygen source: ICSC, accessed: 2019-09-04source: wikidata, accessed: 2019-09-07, Oxygen (liquefied) source: ICSC, accessed: 2019-09-04
    • Appearance: Odourless compressed gas source: ICSC, accessed: 2019-09-04; Liquefied gas. colourless-to-blue extremely cold liquid source: ICSC, accessed: 2019-09-04

Products:

  • 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
  • Ag2SSilver(I) sulfide, Silver sulfide source: wikipedia, accessed: 2019-09-28
    • Other names: Silver sulfide source: wikipedia, accessed: 2019-09-28source: wikidata, accessed: 2019-09-02, Ag2S source: wikidata, accessed: 2019-09-02, Silver(I) sulfide source: wikidata, accessed: 2019-09-02
    • Appearance: Grayish-black crystal source: wikipedia, accessed: 2019-09-28