13H2S + 4Ca3(AsO4)2 → Ca(HSO4)2 + 8H3AsO3 + 11CaS
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The reaction of hydrogen sulfide and calcium arsenate yields calcium hydrogensulfate, arsenous acid, and calcium sulfide (Other reactions are here). This reaction is an oxidation-reduction reaction and is classified as follows:
Table of contents
Reaction data
Chemical equation
- Reaction of hydrogen sulfide and calcium arsenate
General equation
- Reaction of reducing species and reducible species
- Reducing speciesReducing agent + Reducible speciesOxidizing agent ⟶ ProductOxidation product + ProductReduction product
Oxidation state of each atom
- Reaction of hydrogen sulfide and calcium arsenate
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| H2S | Hydrogen sulfide | 13 | Reducing | Reducing |
| Ca3(AsO4)2 | Calcium arsenate | 4 | Oxidizing | Reducible |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| Ca(HSO4)2 | Calcium hydrogensulfate | 1 | Oxidized | – |
| H3AsO3 | Arsenous acid | 8 | Reduced | – |
| CaS | Calcium sulfide | 11 | – | – |
Thermodynamic changes
Thermodynamic data of reactants
| Chemical formula | Standard enthalpy of formation ΔfH° kJ · mol−1 | Standard Gibbs energy of formation ΔfG° kJ · mol−1 | Standard molar entropy S° J · K−1 · mol−1 | Standard molar heat capacity at constant pressure Cp° J · K−1 · mol−1 |
|---|---|---|---|---|
| H2S (g) | -20.63[1] | -33.56[1] | 205.79[1] | 34.23[1] |
| H2S (ao) | -39.7[1] | -27.83[1] | 121[1] | – |
| Ca3(AsO4)2 (cr) | -3298.7[1] | -3063.0[1] | 226[1] | – |
| Ca3(AsO4)2 (cr) hydrated precipitate | -3343[1] | – | – | – |
* (g):Gas, (ao):Un-ionized aqueous solution, (cr):Crystalline solid
Thermodynamic data of products
| Chemical formula | Standard enthalpy of formation ΔfH° kJ · mol−1 | Standard Gibbs energy of formation ΔfG° kJ · mol−1 | Standard molar entropy S° J · K−1 · mol−1 | Standard molar heat capacity at constant pressure Cp° J · K−1 · mol−1 |
|---|---|---|---|---|
| Ca(HSO4)2 | – | – | – | – |
| H3AsO3 (ao) | -742.2[1] | -639.80[1] | 195.0[1] | – |
| H3AsO3 (aq) | -742.2[1] | – | – | – |
| CaS (cr) | -482.4[1] | -477.4[1] | 56.5[1] | 47.40[1] |
| CaS (g) | – | – | – | – |
* (ao):Un-ionized aqueous solution, (aq):Aqueous solution, (cr):Crystalline solid, (g):Gas
References
List of references
- 1Janiel J. Reed (1989)The NBS Tables of Chemical Thermodynamic Properties: Selected Values for Inorganic and C1 and C2 Organic Substances in SI UnitsNational Institute of Standards and Technology (NIST)
- ^ ΔfH°, -20.63 kJ · mol−1
- ^ ΔfG°, -33.56 kJ · mol−1
- ^ S°, 205.79 J · K−1 · mol−1
- ^ Cp°, 34.23 J · K−1 · mol−1
- ^ ΔfH°, -39.7 kJ · mol−1
- ^ ΔfG°, -27.83 kJ · mol−1
- ^ S°, 121. J · K−1 · mol−1
- ^ ΔfH°, -3298.7 kJ · mol−1
- ^ ΔfG°, -3063.0 kJ · mol−1
- ^ S°, 226. J · K−1 · mol−1
- ^ ΔfH°, -3343. kJ · mol−1
- ^ ΔfH°, -742.2 kJ · mol−1
- ^ ΔfG°, -639.80 kJ · mol−1
- ^ S°, 195.0 J · K−1 · mol−1
- ^ ΔfH°, -742.2 kJ · mol−1
- ^ ΔfH°, -482.4 kJ · mol−1
- ^ ΔfG°, -477.4 kJ · mol−1
- ^ S°, 56.5 J · K−1 · mol−1
- ^ Cp°, 47.40 J · K−1 · mol−1