18NaCl + 2K2Cr2O7 + 22H+ 🔥→ 18Na+ + 3Cl2O↑ + 4CrCl3 + 4K+ + 11H2O
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- Reaction of sodium chloride and potassium dichromate under acidic condition
- 18NaClSodium chloride + 2K2Cr2O7Potassium dichromate + 22H+Hydrogen ion18Na+Sodium ion + 3Cl2O↑Dichlorine monoxide + 4CrCl3Chromium(III) chloride + 4K+Potassium ion + 11H2OWater🔥⟶
The reaction of sodium chloride, potassium dichromate, and hydrogen ion yields sodium ion, dichlorine monoxide, chromium(III) chloride, potassium 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 sodium chloride and potassium dichromate under acidic condition
- 18NaClSodium chloride + 2K2Cr2O7Potassium dichromate + 22H+Hydrogen ion18Na+Sodium ion + 3Cl2O↑Dichlorine monoxide + 4CrCl3Chromium(III) chloride + 4K+Potassium ion + 11H2OWater🔥⟶
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 sodium chloride and potassium dichromate under acidic condition
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| NaCl | Sodium chloride | 18 | Reducing | Hardly oxidizable |
| K2Cr2O7 | Potassium dichromate | 2 | Oxidizing | Oxidizing under acidic condition |
| H+ | Hydrogen ion | 22 | – | Hydrogen ion |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| Na+ | Sodium ion | 18 | – | – |
| Cl2O | Dichlorine monoxide | 3 | Oxidized | – |
| CrCl3 | Chromium(III) chloride | 4 | Reduced | – |
| K+ | Potassium ion | 4 | – | – |
| H2O | Water | 11 | – | Water |
Thermodynamic changes
Changes in standard condition
- Reaction of sodium chloride and potassium dichromate under acidic condition◆
ΔrG 705.1 kJ/mol K 0.30 × 10−123 pK 123.53
| 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 | 859.8 | 705.1 | 518.8 | – |
per 1 mol of | 47.77 | 39.17 | 28.82 | – |
per 1 mol of | 429.9 | 352.6 | 259.4 | – |
per 1 mol of Hydrogen ion | 39.08 | 32.05 | 23.58 | – |
per 1 mol of Sodium ion | 47.77 | 39.17 | 28.82 | – |
per 1 mol of | 286.6 | 235.0 | 172.9 | – |
per 1 mol of | 214.9 | 176.3 | 129.7 | – |
per 1 mol of Potassium ion | 214.9 | 176.3 | 129.7 | – |
per 1 mol of | 78.16 | 64.10 | 47.16 | – |
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 |
|---|---|---|---|---|
| NaCl (cr) | -411.153[1] | -384.138[1] | 72.13[1] | 50.50[1] |
| NaCl (g) | -176.65[1] | -196.66[1] | 229.81[1] | 35.77[1] |
| NaCl (ai) | -407.27[1] | -393.133[1] | 115.5[1] | -90.0[1] |
| K2Cr2O7 (cr) | -2061.5[1] | -1881.8[1] | 291.2[1] | 219.24[1] |
| K2Cr2O7 (ai) | -1994.9[1] | -1867.6[1] | 466.9[1] | – |
| H+ (g) | 1536.202[1] | – | – | – |
| H+ (ao) | 0[1] | 0[1] | 0[1] | 0[1] |
* (cr):Crystalline solid, (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 |
|---|---|---|---|---|
| Na+ (g) | 609.358[1] | – | – | – |
| Na+ (ao) | -240.12[1] | -261.905[1] | 59.0[1] | 46.4[1] |
| Cl2O (g) | 80.3[1] | 97.9[1] | 266.21[1] | 45.40[1] |
| CrCl3 (cr) | -556.5[1] | -486.1[1] | 123.0[1] | 91.80[1] |
| K+ (g) | 514.26[1] | – | – | – |
| K+ (ao) | -252.38[1] | -283.27[1] | 102.5[1] | 21.8[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] |
* (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°, -411.153 kJ · mol−1
- ^ ΔfG°, -384.138 kJ · mol−1
- ^ S°, 72.13 J · K−1 · mol−1
- ^ Cp°, 50.50 J · K−1 · mol−1
- ^ ΔfH°, -176.65 kJ · mol−1
- ^ ΔfG°, -196.66 kJ · mol−1
- ^ S°, 229.81 J · K−1 · mol−1
- ^ Cp°, 35.77 J · K−1 · mol−1
- ^ ΔfH°, -407.27 kJ · mol−1
- ^ ΔfG°, -393.133 kJ · mol−1
- ^ S°, 115.5 J · K−1 · mol−1
- ^ Cp°, -90.0 J · K−1 · mol−1
- ^ ΔfH°, -2061.5 kJ · mol−1
- ^ ΔfG°, -1881.8 kJ · mol−1
- ^ S°, 291.2 J · K−1 · mol−1
- ^ Cp°, 219.24 J · K−1 · mol−1
- ^ ΔfH°, -1994.9 kJ · mol−1
- ^ ΔfG°, -1867.6 kJ · mol−1
- ^ S°, 466.9 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°, 609.358 kJ · mol−1
- ^ ΔfH°, -240.12 kJ · mol−1
- ^ ΔfG°, -261.905 kJ · mol−1
- ^ S°, 59.0 J · K−1 · mol−1
- ^ Cp°, 46.4 J · K−1 · mol−1
- ^ ΔfH°, 80.3 kJ · mol−1
- ^ ΔfG°, 97.9 kJ · mol−1
- ^ S°, 266.21 J · K−1 · mol−1
- ^ Cp°, 45.40 J · K−1 · mol−1
- ^ ΔfH°, -556.5 kJ · mol−1
- ^ ΔfG°, -486.1 kJ · mol−1
- ^ S°, 123.0 J · K−1 · mol−1
- ^ Cp°, 91.80 J · K−1 · mol−1
- ^ ΔfH°, 514.26 kJ · mol−1
- ^ ΔfH°, -252.38 kJ · mol−1
- ^ ΔfG°, -283.27 kJ · mol−1
- ^ S°, 102.5 J · K−1 · mol−1
- ^ Cp°, 21.8 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