3H2SeO4 + 2e− → H2SeO3 + 2HSeO4− + H2O
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- Reduction of selenic acid
Reduction of selenic acid yields selenous acid, hydrogenselenate ion, and water (Other reactions are here). This reaction is an oxidation-reduction reaction and is classified as follows:
Table of contents
Reaction data
Chemical equation
- Reduction of selenic acid
General equation
- Reduction of reducible species
- ReactantOxidizing agent + e− ⟶ ProductReduction product
Oxidation state of each atom
- Reduction of selenic acid
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| H2SeO4 | Selenic acid | 3 | Oxidizing | – |
| e− | Electron | 2 | – | Electron |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| H2SeO3 | Selenous acid | 1 | Reduced | – |
| HSeO4− | Hydrogenselenate ion | 2 | – | – |
| H2O | Water | 1 | – | – |
Thermodynamic changes
Changes in standard condition (1)
- Reduction of selenic acid
| Standard enthalpy of reaction ΔrH° kJ · mol−1 | Standard Gibbs energy of reaction ΔrG° kJ · mol−1 | Standard entropy of reaction ΔrS° J · K−1 · mol−1 | Standard heat capacity of reaction at constant pressure ΔrCp° J · K−1 · mol−1 | |
|---|---|---|---|---|
per 1 mol of Equation | −366.2 | – | – | – |
per 1 mol of | −122.1 | – | – | – |
per 1 mol of Electron | −183.1 | – | – | – |
per 1 mol of | −366.2 | – | – | – |
per 1 mol of Hydrogenselenate ion | −183.1 | – | – | – |
per 1 mol of | −366.2 | – | – | – |
Changes in standard condition (2)
- Reduction of selenic acid
| Standard enthalpy of reaction ΔrH° kJ · mol−1 | Standard Gibbs energy of reaction ΔrG° kJ · mol−1 | Standard entropy of reaction ΔrS° J · K−1 · mol−1 | Standard heat capacity of reaction at constant pressure ΔrCp° J · K−1 · mol−1 | |
|---|---|---|---|---|
per 1 mol of Equation | −366.0 | – | – | – |
per 1 mol of | −122.0 | – | – | – |
per 1 mol of Electron | −183.0 | – | – | – |
per 1 mol of | −366.0 | – | – | – |
per 1 mol of Hydrogenselenate ion | −183.0 | – | – | – |
per 1 mol of | −366.0 | – | – | – |
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 |
|---|---|---|---|---|
| H2SeO4 (cr) | -530.1[1] | – | – | – |
| H2SeO4 (cr) 1 hydrate | -840.6[1] | – | – | – |
| H2SeO4 (l) 1 hydrate | -820.5[1] | – | – | – |
| e− | – | – | – | – |
* (cr):Crystalline solid, (l):Liquid
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 |
|---|---|---|---|---|
| H2SeO3 (cr) | -524.46[1] | – | – | – |
| H2SeO3 (ao) | -507.48[1] | -426.14[1] | 207.9[1] | – |
| H2SeO3 (aq) | -507.27[1] | – | – | – |
| HSeO4− (ao) | -581.6[1] | -452.2[1] | 149.4[1] | – |
| H2O (cr) | – | – | – | – |
| H2O (l) | -285.830[1] | -237.129[1] | 69.91[1] | 75.291[1] |
| H2O (g) | -241.818[1] | -228.572[1] | 188.825[1] | 33.577[1] |
* (cr):Crystalline solid, (ao):Un-ionized aqueous solution, (aq):Aqueous solution, (l):Liquid, (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°, -530.1 kJ · mol−1
- ^ ΔfH°, -840.6 kJ · mol−1
- ^ ΔfH°, -820.5 kJ · mol−1
- ^ ΔfH°, -524.46 kJ · mol−1
- ^ ΔfH°, -507.48 kJ · mol−1
- ^ ΔfG°, -426.14 kJ · mol−1
- ^ S°, 207.9 J · K−1 · mol−1
- ^ ΔfH°, -507.27 kJ · mol−1
- ^ ΔfH°, -581.6 kJ · mol−1
- ^ ΔfG°, -452.2 kJ · mol−1
- ^ S°, 149.4 J · K−1 · mol−1
- ^ ΔfH°, -285.830 kJ · mol−1
- ^ ΔfG°, -237.129 kJ · mol−1
- ^ S°, 69.91 J · K−1 · mol−1
- ^ Cp°, 75.291 J · K−1 · mol−1
- ^ ΔfH°, -241.818 kJ · mol−1
- ^ ΔfG°, -228.572 kJ · mol−1
- ^ S°, 188.825 J · K−1 · mol−1
- ^ Cp°, 33.577 J · K−1 · mol−1