3 Mg + 5 Na2SO3 + 10 HCl → 3 MgSO4 + 2 H2S + 10 NaCl + 3 H2O
This is an acid-base reaction (neutralization): Na2SO3 is a base, HCl is an acid.
This is an oxidation-reduction (redox) reaction:
2 SIV + 12 e- → 2 S-II (reduction)
3 SIV - 6 e- → 3 SVI (oxidation)
3 Mg0 - 6 e- → 3 MgII (oxidation)
Na2SO3 is an oxidizing agent, Na2SO3 is a reducing agent, Mg is a reducing agent.
Reactants:
- Mg
- Na2SO3 – Sodium sulfite
- HCl – Chlorane , Hydrogen chloride
- Other names: Hydrochloric acid , M , Uriatic acid
- Appearance: Colorless, transparent liquid, fumes in air if concentrated ; Colorless gas ; Colourless compressed liquefied gas with pungent odour ; Colorless to slightly yellow gas with a pungent, irritating odor. [Note: Shipped as a liquefied compressed gas.]
Products:
- MgSO4 – Magnesium sulfate
- H2S – Hydrogen sulfide
- Other names: D , Ihydrogen monosulfide|Dihydrogen sulfide|Sewer gas|Sulfane|Sulfurated hydrogen|Sulfureted hydrogen|Sulfuretted hydrogen|Sulfur hydride|Hydrosulfuric acid|Hydrothionic acid|Thiohydroxic acid|Sulfhydric acid}} , Hydrosulfuric acid
- Appearance: Colorless gas ; Colourless compressed liquefied gas with characteristic odour of rotten eggs ; Colorless gas with a strong odor of rotten eggs. [Note: Sense of smell becomes rapidly fatigued & can NOT be relied upon to warn of the continuous presence of H2S. Shipped as a liquefied compressed gas.]
- NaCl – Sodium chloride
- H2O – Water, oxidane