H2 + 2KSCN 🔥→ KHS + KCN + HSCN
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The reaction of and potassium thiocyanate yields potassium hydrogensulfide, potassium cyanide, and thiocyanic acid (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 and potassium thiocyanate
General equation
- Reaction of reducing species and reducible species
- Reducing speciesReducing agent + Reducible speciesOxidizing agent ⟶ ProductOxidation product + ProductReduction product
Oxidation state of each atom
- Reaction of and potassium thiocyanate
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| 1 | Reducing | Reducing | ||
| KSCN | Potassium thiocyanate | 2 | Oxidizing | Reducible |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| KHS | Potassium hydrogensulfide | 1 | Oxidized | – |
| KCN | Potassium cyanide | 1 | Reduced | – |
| HSCN | Thiocyanic acid | 1 | Oxidized | – |
Thermodynamic changes
Changes in aqueous solution (1)
- Reaction of and potassium thiocyanate◆
ΔrG 79.0 kJ/mol K 0.14 × 10−13 pK 13.84
| 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 | – | 79.0 | – | – |
| – | 79.0 | – | – | |
per 1 mol of | – | 39.5 | – | – |
per 1 mol of | – | 79.0 | – | – |
per 1 mol of | – | 79.0 | – | – |
per 1 mol of | – | 79.0 | – | – |
Changes in aqueous solution (2)
- Reaction of and potassium thiocyanate◆
ΔrG 74.1 kJ/mol K 0.10 × 10−12 pK 12.98
| 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 | 60.9 | 74.1 | −565 | – |
| 60.9 | 74.1 | −565 | – | |
per 1 mol of | 30.4 | 37.0 | −283 | – |
per 1 mol of | 60.9 | 74.1 | −565 | – |
per 1 mol of | 60.9 | 74.1 | −565 | – |
per 1 mol of | 60.9 | 74.1 | −565 | – |
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 |
|---|---|---|---|---|
| (g) | 0[1] | 0[1] | 130.684[1] | 28.824[1] |
| (ao) | -4.2[1] | 17.6[1] | 577[1] | – |
| KSCN (cr) | -200.16[1] | -178.31[1] | 124.26[1] | 88.53[1] |
| KSCN (ai) | -175.94[1] | -190.56[1] | 246.9[1] | -18.4[1] |
* (g):Gas, (ao):Un-ionized aqueous solution, (cr):Crystalline solid, (ai):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 |
|---|---|---|---|---|
| KHS (cr) | -265.10[1] | – | – | 75.31[1] |
| KHS (ai) | -269.9[1] | -271.19[1] | 165.3[1] | – |
| KHS (cr) 0.25 hydrate | -337.2[1] | – | – | – |
| KCN (cr) | -113.0[1] | -101.86[1] | 128.49[1] | 66.27[1] |
| KCN (g) | 90.8[1] | 64.17[1] | 261.90[1] | 52.34[1] |
| KCN (ai) | -101.7[1] | -110.9[1] | 196.6[1] | – |
| HSCN (ai) | 76.44[1] | 92.71[1] | 144.3[1] | -40.2[1] |
| HSCN (ao) | – | 97.56[1] | – | – |
* (cr):Crystalline solid, (ai):Ionized aqueous solution, (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°, 0 kJ · mol−1
- ^ ΔfG°, 0 kJ · mol−1
- ^ S°, 130.684 J · K−1 · mol−1
- ^ Cp°, 28.824 J · K−1 · mol−1
- ^ ΔfH°, -4.2 kJ · mol−1
- ^ ΔfG°, 17.6 kJ · mol−1
- ^ S°, 577 J · K−1 · mol−1
- ^ ΔfH°, -200.16 kJ · mol−1
- ^ ΔfG°, -178.31 kJ · mol−1
- ^ S°, 124.26 J · K−1 · mol−1
- ^ Cp°, 88.53 J · K−1 · mol−1
- ^ ΔfH°, -175.94 kJ · mol−1
- ^ ΔfG°, -190.56 kJ · mol−1
- ^ S°, 246.9 J · K−1 · mol−1
- ^ Cp°, -18.4 J · K−1 · mol−1
- ^ ΔfH°, -265.10 kJ · mol−1
- ^ Cp°, 75.31 J · K−1 · mol−1
- ^ ΔfH°, -269.9 kJ · mol−1
- ^ ΔfG°, -271.19 kJ · mol−1
- ^ S°, 165.3 J · K−1 · mol−1
- ^ ΔfH°, -337.2 kJ · mol−1
- ^ ΔfH°, -113.0 kJ · mol−1
- ^ ΔfG°, -101.86 kJ · mol−1
- ^ S°, 128.49 J · K−1 · mol−1
- ^ Cp°, 66.27 J · K−1 · mol−1
- ^ ΔfH°, 90.8 kJ · mol−1
- ^ ΔfG°, 64.17 kJ · mol−1
- ^ S°, 261.90 J · K−1 · mol−1
- ^ Cp°, 52.34 J · K−1 · mol−1
- ^ ΔfH°, -101.7 kJ · mol−1
- ^ ΔfG°, -110.9 kJ · mol−1
- ^ S°, 196.6 J · K−1 · mol−1
- ^ ΔfH°, 76.44 kJ · mol−1
- ^ ΔfG°, 92.71 kJ · mol−1
- ^ S°, 144.3 J · K−1 · mol−1
- ^ Cp°, -40.2 J · K−1 · mol−1
- ^ ΔfG°, 97.56 kJ · mol−1