6KSCN + 3HNO3 → K2SO3 + 2K2S + 3N2↑ + 3HSCN + 3CO2↑
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- Reaction of potassium thiocyanate and nitric acid
The reaction of potassium thiocyanate and nitric acid yields potassium sulfite, potassium sulfide, , thiocyanic acid, and carbon dioxide (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 potassium thiocyanate and nitric acid
General equation
- Reaction of reducing species and oxidizing species
- Reducing speciesReducing agent + Oxidizing speciesOxidizing agent ⟶ ProductOxidation product + ProductReduction product
Oxidation state of each atom
- Reaction of potassium thiocyanate and nitric acid
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| KSCN | Potassium thiocyanate | 6 | Reducing | Reducing |
| HNO3 | Nitric acid | 3 | Oxidizing | Oxidizing |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| K2SO3 | Potassium sulfite | 1 | Oxidized | – |
| K2S | Potassium sulfide | 2 | – | – |
| 3 | Redoxed product | – | ||
| HSCN | Thiocyanic acid | 3 | – | – |
| CO2 | Carbon dioxide | 3 | – | – |
Thermodynamic changes
Changes in aqueous solution (1)
- Reaction of potassium thiocyanate and nitric acid◆
ΔrG −1427.8 kJ/mol K 1.38 × 10250 pK −250.14
| 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 | – | −1427.8 | – | – |
per 1 mol of | – | −237.97 | – | – |
per 1 mol of | – | −475.93 | – | – |
per 1 mol of | – | −1427.8 | – | – |
per 1 mol of | – | −713.90 | – | – |
| – | −475.93 | – | – | |
per 1 mol of | – | −475.93 | – | – |
per 1 mol of | – | −475.93 | – | – |
Changes in aqueous solution (2)
- Reaction of potassium thiocyanate and nitric acid◆
ΔrG −1402.7 kJ/mol K 5.53 × 10245 pK −245.74
| 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 | – | −1402.7 | – | – |
per 1 mol of | – | −233.78 | – | – |
per 1 mol of | – | −467.57 | – | – |
per 1 mol of | – | −1402.7 | – | – |
per 1 mol of | – | −701.35 | – | – |
| – | −467.57 | – | – | |
per 1 mol of | – | −467.57 | – | – |
per 1 mol of | – | −467.57 | – | – |
Changes in aqueous solution (3)
- Reaction of potassium thiocyanate and nitric acid◆
ΔrG −1442.3 kJ/mol K 4.79 × 10252 pK −252.68
| 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 | −1356.6 | −1442.3 | 285 | – |
per 1 mol of | −226.10 | −240.38 | 47.5 | – |
per 1 mol of | −452.20 | −480.77 | 95.0 | – |
per 1 mol of | −1356.6 | −1442.3 | 285 | – |
per 1 mol of | −678.30 | −721.15 | 143 | – |
| −452.20 | −480.77 | 95.0 | – | |
per 1 mol of | −452.20 | −480.77 | 95.0 | – |
per 1 mol of | −452.20 | −480.77 | 95.0 | – |
Changes in aqueous solution (4)
- Reaction of potassium thiocyanate and nitric acid◆
ΔrG −1417.2 kJ/mol K 1.92 × 10248 pK −248.28
| 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 | −1417.5 | −1417.2 | −3 | – |
per 1 mol of | −236.25 | −236.20 | −0.5 | – |
per 1 mol of | −472.50 | −472.40 | −1 | – |
per 1 mol of | −1417.5 | −1417.2 | −3 | – |
per 1 mol of | −708.75 | −708.60 | −2 | – |
| −472.50 | −472.40 | −1 | – | |
per 1 mol of | −472.50 | −472.40 | −1 | – |
per 1 mol of | −472.50 | −472.40 | −1 | – |
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 |
|---|---|---|---|---|
| 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] |
| HNO3 (l) | -174.10[1] | -80.71[1] | 155.60[1] | 109.87[1] |
| HNO3 (g) | -135.06[1] | -74.72[1] | 266.38[1] | 53.35[1] |
| HNO3 (ai) | -207.36[1] | -111.25[1] | 146.4[1] | -86.6[1] |
| HNO3 (l) 1 hydrate | -473.46[1] | -328.77[1] | 216.90[1] | 182.46[1] |
| HNO3 (l) 3 hydrate | -1056.04[1] | -811.09[1] | 346.98[1] | 325.14[1] |
* (cr):Crystalline solid, (ai):Ionized aqueous solution, (l):Liquid, (g):Gas
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 |
|---|---|---|---|---|
| K2SO3 (cr) | -1125.5[1] | – | – | – |
| K2SO3 (ai) | -1140.1[1] | -1053.1[1] | 176[1] | – |
| K2S (cr) | -380.7[1] | -364.0[1] | 105[1] | – |
| K2S (ai) | -471.5[1] | -480.7[1] | 190.4[1] | – |
| K2S (cr) 2 hydrate | -975.3[1] | – | – | – |
| K2S (cr) 5 hydrate | -1871.5[1] | – | – | – |
| (g) | 0[1] | 0[1] | 191.61[1] | 29.125[1] |
| HSCN (ai) | 76.44[1] | 92.71[1] | 144.3[1] | -40.2[1] |
| HSCN (ao) | – | 97.56[1] | – | – |
| CO2 (g) | -393.509[1] | -394.359[1] | 213.74[1] | 37.11[1] |
| CO2 (ao) | -413.80[1] | -385.98[1] | 117.6[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°, -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°, -174.10 kJ · mol−1
- ^ ΔfG°, -80.71 kJ · mol−1
- ^ S°, 155.60 J · K−1 · mol−1
- ^ Cp°, 109.87 J · K−1 · mol−1
- ^ ΔfH°, -135.06 kJ · mol−1
- ^ ΔfG°, -74.72 kJ · mol−1
- ^ S°, 266.38 J · K−1 · mol−1
- ^ Cp°, 53.35 J · K−1 · mol−1
- ^ ΔfH°, -207.36 kJ · mol−1
- ^ ΔfG°, -111.25 kJ · mol−1
- ^ S°, 146.4 J · K−1 · mol−1
- ^ Cp°, -86.6 J · K−1 · mol−1
- ^ ΔfH°, -473.46 kJ · mol−1
- ^ ΔfG°, -328.77 kJ · mol−1
- ^ S°, 216.90 J · K−1 · mol−1
- ^ Cp°, 182.46 J · K−1 · mol−1
- ^ ΔfH°, -1056.04 kJ · mol−1
- ^ ΔfG°, -811.09 kJ · mol−1
- ^ S°, 346.98 J · K−1 · mol−1
- ^ Cp°, 325.14 J · K−1 · mol−1
- ^ ΔfH°, -1125.5 kJ · mol−1
- ^ ΔfH°, -1140.1 kJ · mol−1
- ^ ΔfG°, -1053.1 kJ · mol−1
- ^ S°, 176. J · K−1 · mol−1
- ^ ΔfH°, -380.7 kJ · mol−1
- ^ ΔfG°, -364.0 kJ · mol−1
- ^ S°, 105. J · K−1 · mol−1
- ^ ΔfH°, -471.5 kJ · mol−1
- ^ ΔfG°, -480.7 kJ · mol−1
- ^ S°, 190.4 J · K−1 · mol−1
- ^ ΔfH°, -975.3 kJ · mol−1
- ^ ΔfH°, -1871.5 kJ · mol−1
- ^ ΔfH°, 0 kJ · mol−1
- ^ ΔfG°, 0 kJ · mol−1
- ^ S°, 191.61 J · K−1 · mol−1
- ^ Cp°, 29.125 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
- ^ ΔfH°, -393.509 kJ · mol−1
- ^ ΔfG°, -394.359 kJ · mol−1
- ^ S°, 213.74 J · K−1 · mol−1
- ^ Cp°, 37.11 J · K−1 · mol−1
- ^ ΔfH°, -413.80 kJ · mol−1
- ^ ΔfG°, -385.98 kJ · mol−1
- ^ S°, 117.6 J · K−1 · mol−1