3HCl + CaCr2O7 + 6H+ → Ca(ClO)2 + HClO + 2Cr3+ + 4H2O
Last updated:
- Reaction of hydrogen chloride and calcium dichromate under acidic condition
- 3HClHydrogen chloride + CaCr2O7Calcium dichromate + 6H+Hydrogen ionCa(ClO)2Calcium hypochlorite + HClOHypochlorous acid + 2Cr3+Chromium(III) ion + 4H2OWater⟶
The reaction of hydrogen chloride, calcium dichromate, and hydrogen ion yields calcium hypochlorite, hypochlorous acid, chromium(III) 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
- Reaction of hydrogen chloride and calcium dichromate under acidic condition
- 3HClHydrogen chloride + CaCr2O7Calcium dichromate + 6H+Hydrogen ionCa(ClO)2Calcium hypochlorite + HClOHypochlorous acid + 2Cr3+Chromium(III) ion + 4H2OWater⟶
General equation
- Reaction of hardly oxidizable species and oxidizing species under acidic condition
- Hardly oxidizable speciesReducing agent + Oxidizing speciesOxidizing agent + H+Non-redox agent ⟶ ProductOxidation product + ProductReduction product + H2ONon-redox product
Oxidation state of each atom
- Reaction of hydrogen chloride and calcium dichromate under acidic condition
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| HCl | Hydrogen chloride | 3 | Reducing | Hardly oxidizable |
| CaCr2O7 | Calcium dichromate | 1 | Oxidizing | Oxidizing under acidic condition |
| H+ | Hydrogen ion | 6 | – | Hydrogen ion |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| Ca(ClO)2 | Calcium hypochlorite | 1 | Oxidized | – |
| HClO | Hypochlorous acid | 1 | Oxidized | – |
| Cr3+ | Chromium(III) ion | 2 | Reduced | – |
| H2O | Water | 4 | – | Water |
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 |
|---|---|---|---|---|
| HCl (g) | -92.307[1] | -95.299[1] | 186.908[1] | 29.12[1] |
| HCl (ai) | -167.159[1] | -131.228[1] | 56.5[1] | -136.4[1] |
| CaCr2O7 | – | – | – | – |
| H+ (g) | 1536.202[1] | – | – | – |
| H+ (ao) | 0[1] | 0[1] | 0[1] | 0[1] |
* (g):Gas, (ai):Ionized aqueous solution, (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 |
|---|---|---|---|---|
| Ca(ClO)2 (aq) | -754.4[1] | – | – | – |
| HClO (g) | -78.7[1] | -66.1[1] | 236.67[1] | 37.15[1] |
| HClO (ao) | -120.9[1] | -79.9[1] | 142[1] | – |
| Cr3+ (g) | 5648.4[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] |
* (aq):Aqueous solution, (g):Gas, (ao):Un-ionized aqueous solution, (cr):Crystalline solid, (l):Liquid
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°, -92.307 kJ · mol−1
- ^ ΔfG°, -95.299 kJ · mol−1
- ^ S°, 186.908 J · K−1 · mol−1
- ^ Cp°, 29.12 J · K−1 · mol−1
- ^ ΔfH°, -167.159 kJ · mol−1
- ^ ΔfG°, -131.228 kJ · mol−1
- ^ S°, 56.5 J · K−1 · mol−1
- ^ Cp°, -136.4 J · K−1 · mol−1
- ^ ΔfH°, 1536.202 kJ · mol−1
- ^ ΔfH°, 0 kJ · mol−1
- ^ ΔfG°, 0 kJ · mol−1
- ^ S°, 0 J · K−1 · mol−1
- ^ Cp°, 0 J · K−1 · mol−1
- ^ ΔfH°, -754.4 kJ · mol−1
- ^ ΔfH°, -78.7 kJ · mol−1
- ^ ΔfG°, -66.1 kJ · mol−1
- ^ S°, 236.67 J · K−1 · mol−1
- ^ Cp°, 37.15 J · K−1 · mol−1
- ^ ΔfH°, -120.9 kJ · mol−1
- ^ ΔfG°, -79.9 kJ · mol−1
- ^ S°, 142. J · K−1 · mol−1
- ^ ΔfH°, 5648.4 kJ · 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