4HClO4 💧⚡→ 4ClO2↑ + 3O2↑ + 2H2O
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- Electrolysis of aqueous perchloric acid without water as reactant
Electrolysis of aqueous perchloric acid yields chlorine dioxide, , 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
- Electrolysis of aqueous perchloric acid without water as reactant
General equation
- Electrolysis of aqueous solution without water as reactant
- Miscible with water/Very soluble in water/Soluble in waterSelf redox agent💧⚡⟶ ProductOxidation product + ProductReduction product
Oxidation state of each atom
- Electrolysis of aqueous perchloric acid without water as reactant
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| HClO4 | Perchloric acid | 4 | Self redox agent | Very soluble in water |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| ClO2 | Chlorine dioxide | 4 | Reduced | – |
| 3 | Oxidized | – | ||
| H2O | Water | 2 | – | – |
Thermodynamic changes
Changes in standard condition
- Electrolysis of aqueous perchloric acid without water as reactant
| 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 | 0.7 | – | – | – |
per 1 mol of | 0.17 | – | – | – |
per 1 mol of | 0.17 | – | – | – |
| 0.23 | – | – | – | |
per 1 mol of | 0.35 | – | – | – |
Changes in aqueous solution (1)
- Electrolysis of aqueous perchloric acid without water as reactant◆
ΔrG 41.8 kJ/mol K 0.48 × 10−7 pK 7.32
| 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 | 355.7 | 41.8 | 1054.6 | – |
per 1 mol of | 88.92 | 10.4 | 263.65 | – |
per 1 mol of | 88.92 | 10.4 | 263.65 | – |
| 118.6 | 13.9 | 351.53 | – | |
per 1 mol of | 177.8 | 20.9 | 527.30 | – |
Changes in aqueous solution (2)
- Electrolysis of aqueous perchloric acid without water as reactant◆
ΔrG 91.0 kJ/mol K 0.11 × 10−15 pK 15.94
| 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 | 320.6 | 91.0 | 771.9 | – |
per 1 mol of | 80.15 | 22.8 | 193.0 | – |
per 1 mol of | 80.15 | 22.8 | 193.0 | – |
| 106.9 | 30.3 | 257.3 | – | |
per 1 mol of | 160.3 | 45.5 | 385.9 | – |
Changes in aqueous solution (3)
- Electrolysis of aqueous perchloric acid without water as reactant◆
ΔrG 40.2 kJ/mol K 0.91 × 10−7 pK 7.04
| 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 | 245.3 | 40.2 | 686.4 | – |
per 1 mol of | 61.33 | 10.1 | 171.6 | – |
per 1 mol of | 61.33 | 10.1 | 171.6 | – |
| 81.77 | 13.4 | 228.8 | – | |
per 1 mol of | 122.7 | 20.1 | 343.2 | – |
Changes in aqueous solution (4)
- Electrolysis of aqueous perchloric acid without water as reactant◆
ΔrG 89.4 kJ/mol K 0.22 × 10−15 pK 15.66
| 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 | 210.2 | 89.4 | 403.7 | – |
per 1 mol of | 52.55 | 22.4 | 100.9 | – |
per 1 mol of | 52.55 | 22.4 | 100.9 | – |
| 70.07 | 29.8 | 134.6 | – | |
per 1 mol of | 105.1 | 44.7 | 201.8 | – |
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 |
|---|---|---|---|---|
| HClO4 (l) | -40.58[1] | – | – | – |
| HClO4 (ai) | -129.33[1] | -8.52[1] | 182.0[1] | – |
| HClO4 (cr) 1 hydrate | -382.21[1] | – | – | – |
| HClO4 (l) 2 hydrate | -677.98[1] | – | – | – |
* (l):Liquid, (ai):Ionized aqueous solution, (cr):Crystalline solid
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 |
|---|---|---|---|---|
| ClO2 (g) | 102.5[1] | 120.5[1] | 256.84[1] | 41.97[1] |
| ClO2 (ao) | 74.9[1] | 120.1[1] | 164.8[1] | – |
| (g) | 0[1] | 0[1] | 205.138[1] | 29.355[1] |
| (ao) | -11.7[1] | 16.4[1] | 110.9[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°, -40.58 kJ · mol−1
- ^ ΔfH°, -129.33 kJ · mol−1
- ^ ΔfG°, -8.52 kJ · mol−1
- ^ S°, 182.0 J · K−1 · mol−1
- ^ ΔfH°, -382.21 kJ · mol−1
- ^ ΔfH°, -677.98 kJ · mol−1
- ^ ΔfH°, 102.5 kJ · mol−1
- ^ ΔfG°, 120.5 kJ · mol−1
- ^ S°, 256.84 J · K−1 · mol−1
- ^ Cp°, 41.97 J · K−1 · mol−1
- ^ ΔfH°, 74.9 kJ · mol−1
- ^ ΔfG°, 120.1 kJ · mol−1
- ^ S°, 164.8 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°, -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