12HCrO4− + 6e− → Cr + 4H3O+ + 11CrO42−
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Reduction of hydrogenchromate ion yields , hydronium ion, and chromate ion (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 hydrogenchromate ion
General equation
- Reduction of reducible species
- ReactantOxidizing agent + e− ⟶ ProductReduction product
Oxidation state of each atom
- Reduction of hydrogenchromate ion
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| HCrO4− | Hydrogenchromate ion | 12 | Oxidizing | – |
| e− | Electron | 6 | – | Electron |
Products
Thermodynamic changes
Changes in standard condition
- Reduction of hydrogenchromate ion◆
ΔrG 222.6 kJ/mol K 0.10 × 10−38 pK 39.00 - 12HCrO4−Un-ionized aqueous solution + 6e−Crystalline solid + 4H3O+Un-ionized aqueous solution + 11CrO42−Un-ionized aqueous solution⟶
| 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 | −297.6 | 222.6 | −1353.5 | – |
per 1 mol of Hydrogenchromate ion | −24.80 | 18.55 | −112.79 | – |
per 1 mol of Electron | −49.60 | 37.10 | −225.58 | – |
| −297.6 | 222.6 | −1353.5 | – | |
per 1 mol of Hydronium ion | −74.40 | 55.65 | −338.38 | – |
per 1 mol of Chromate ion | −27.05 | 20.24 | −123.05 | – |
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 |
|---|---|---|---|---|
| HCrO4− (ao) | -878.2[1] | -764.7[1] | 184.1[1] | – |
| e− | – | – | – | – |
* (ao):Un-ionized aqueous solution
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 |
|---|---|---|---|---|
| (cr) | 0[1] | 0[1] | 23.77[1] | 23.35[1] |
| (g) | 396.6[1] | 351.8[1] | 174.50[1] | 20.79[1] |
| H3O+ (ao) | -285.830[1] | -237.129[1] | 69.91[1] | 75.291[1] |
| CrO42− (ao) | -881.15[1] | -727.75[1] | 50.21[1] | – |
* (cr):Crystalline solid, (g):Gas, (ao):Un-ionized aqueous solution
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°, -878.2 kJ · mol−1
- ^ ΔfG°, -764.7 kJ · mol−1
- ^ S°, 184.1 J · K−1 · mol−1
- ^ ΔfH°, 0 kJ · mol−1
- ^ ΔfG°, 0 kJ · mol−1
- ^ S°, 23.77 J · K−1 · mol−1
- ^ Cp°, 23.35 J · K−1 · mol−1
- ^ ΔfH°, 396.6 kJ · mol−1
- ^ ΔfG°, 351.8 kJ · mol−1
- ^ S°, 174.50 J · K−1 · mol−1
- ^ Cp°, 20.79 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°, -881.15 kJ · mol−1
- ^ ΔfG°, -727.75 kJ · mol−1
- ^ S°, 50.21 J · K−1 · mol−1