Br2 (aq) + Na2S (aq) → 2 NaBr (aq) + S (s)

This is an oxidation-reduction (redox) reaction:

2 Br0 + 2 e- → 2 Br-I (reduction)

S-II - 2 e- → S0 (oxidation)

Br2 is an oxidizing agent, Na2S is a reducing agent.

This is a precipitation reaction: S is the formed precipitate.

Reactants:

  • Br2
    • Names: Bromine source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02, Molecular bromine source: NIOSH NPG, accessed: 2019-09-02
    • Appearance: Fuming red-to-brown liquid with pungent odour source: ICSC, accessed: 2019-09-04; Dark reddish-brown, fuming liquid with suffocating, irritating fumes. source: NIOSH NPG, accessed: 2019-09-02
  • 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

Products:

  • NaBr – Sodium bromide source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02
    • Other names: Bromide salt of sodium source: wikidata, accessed: 2019-09-02, Trisodium tribromide source: wikidata, accessed: 2019-09-02, NaBr source: wikidata, accessed: 2019-09-02
    • Appearance: White powder, hygroscopic source: wikipedia, accessed: 2019-09-27
  • S
    • Names: Sulfur source: wikidata, accessed: 2019-09-07source: ICSC, accessed: 2019-09-04, S source: wikidata, accessed: 2019-09-07, Sulphur source: wikidata, accessed: 2019-09-07source: ICSC, accessed: 2019-09-04
    • Appearance: Yellow solid in various forms source: ICSC, accessed: 2019-09-04