12HCrO4− → O2 + 6Cr2O72− + 4H3O+ + 4e−
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Oxidation of hydrogenchromate ion yields , dichromate ion, hydronium ion (Other reactions are here). This reaction is an oxidation-reduction reaction and is classified as follows:
Table of contents
Reaction data
Chemical equation
- Oxidation of hydrogenchromate ion
General equation
- Oxidation of oxidizable species
- ReactantReducing agent ⟶ ProductOxidation product + e−
Oxidation state of each atom
- Oxidation of hydrogenchromate ion
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| HCrO4− | Hydrogenchromate ion | 12 | Reducing | – |
Products
Thermodynamic changes
Changes in standard condition (1)
- Oxidation of hydrogenchromate ion◆
ΔrG 421.3 kJ/mol K 0.16 × 10−73 pK 73.81 - 12HCrO4−Un-ionized aqueous solutionGas + 6Cr2O72−Un-ionized aqueous solution + 4H3O+Un-ionized aqueous solution + 4e−⟶
| 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 | 453.3 | 421.3 | −153.0 | – |
per 1 mol of Hydrogenchromate ion | 37.77 | 35.11 | −12.75 | – |
| 453.3 | 421.3 | −153.0 | – | |
per 1 mol of Dichromate ion | 75.55 | 70.22 | −25.50 | – |
per 1 mol of Hydronium ion | 113.3 | 105.3 | −38.25 | – |
per 1 mol of Electron | 113.3 | 105.3 | −38.25 | – |
Changes in standard condition (2)
- Oxidation of hydrogenchromate ion◆
ΔrG 437.7 kJ/mol K 0.21 × 10−76 pK 76.68 - 12HCrO4−Un-ionized aqueous solutionUn-ionized aqueous solution + 6Cr2O72−Un-ionized aqueous solution + 4H3O+Un-ionized aqueous solution + 4e−⟶
| 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 | 441.6 | 437.7 | −247.3 | – |
per 1 mol of Hydrogenchromate ion | 36.80 | 36.48 | −20.61 | – |
| 441.6 | 437.7 | −247.3 | – | |
per 1 mol of Dichromate ion | 73.60 | 72.95 | −41.22 | – |
per 1 mol of Hydronium ion | 110.4 | 109.4 | −61.83 | – |
per 1 mol of Electron | 110.4 | 109.4 | −61.83 | – |
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] | – |
* (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 |
|---|---|---|---|---|
| (g) | 0[1] | 0[1] | 205.138[1] | 29.355[1] |
| (ao) | -11.7[1] | 16.4[1] | 110.9[1] | – |
| Cr2O72− (ao) | -1490.3[1] | -1301.1[1] | 261.9[1] | – |
| H3O+ (ao) | -285.830[1] | -237.129[1] | 69.91[1] | 75.291[1] |
| e− | – | – | – | – |
* (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°, 205.138 J · K−1 · mol−1
- ^ Cp°, 29.355 J · K−1 · mol−1
- ^ ΔfH°, -11.7 kJ · mol−1
- ^ ΔfG°, 16.4 kJ · mol−1
- ^ S°, 110.9 J · K−1 · mol−1
- ^ ΔfH°, -1490.3 kJ · mol−1
- ^ ΔfG°, -1301.1 kJ · mol−1
- ^ S°, 261.9 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