NH4SCN + 3HNO3 → 2N2O3↑ + NH4HCO3 + H2S↑
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The reaction of ammonium thiocyanate and nitric acid yields dinitrogen trioxide, ammonium hydrogencarbonate, and hydrogen sulfide (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 ammonium 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 ammonium thiocyanate and nitric acid
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| NH4SCN | Ammonium thiocyanate | 1 | Reducing | Reducing |
| HNO3 | Nitric acid | 3 | Oxidizing | Oxidizing |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| N2O3 | Dinitrogen trioxide | 2 | Redoxed product | – |
| NH4HCO3 | Ammonium hydrogencarbonate | 1 | – | – |
| H2S | Hydrogen sulfide | 1 | – | – |
Thermodynamic changes
Changes in standard condition
- Reaction of ammonium thiocyanate and nitric acid
| 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 | −101.6 | – | – | – |
per 1 mol of | −101.6 | – | – | – |
per 1 mol of | −33.87 | – | – | – |
per 1 mol of | −50.80 | – | – | – |
per 1 mol of | −101.6 | – | – | – |
per 1 mol of | −101.6 | – | – | – |
Changes in aqueous solution (1)
- Reaction of ammonium thiocyanate and nitric acid◆
ΔrG −100.36 kJ/mol K 3.82 × 1017 pK −17.58
| 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 | 0.46 | −100.36 | 338.1 | – |
per 1 mol of | 0.460 | −100.36 | 338.1 | – |
per 1 mol of | 0.153 | −33.453 | 112.7 | – |
per 1 mol of | 0.230 | −50.180 | 169.1 | – |
per 1 mol of | 0.460 | −100.36 | 338.1 | – |
per 1 mol of | 0.460 | −100.36 | 338.1 | – |
Changes in aqueous solution (2)
- Reaction of ammonium thiocyanate and nitric acid◆
ΔrG −94.63 kJ/mol K 3.79 × 1016 pK −16.58
| 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 | −18.6 | −94.63 | 253 | – |
per 1 mol of | −18.6 | −94.63 | 253 | – |
per 1 mol of | −6.20 | −31.54 | 84.3 | – |
per 1 mol of | −9.30 | −47.31 | 127 | – |
per 1 mol of | −18.6 | −94.63 | 253 | – |
per 1 mol of | −18.6 | −94.63 | 253 | – |
Changes in aqueous solution (3)
- Reaction of ammonium thiocyanate and nitric acid
| 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 | 3.3 | – | – | – |
per 1 mol of | 3.3 | – | – | – |
per 1 mol of | 1.1 | – | – | – |
per 1 mol of | 1.6 | – | – | – |
per 1 mol of | 3.3 | – | – | – |
per 1 mol of | 3.3 | – | – | – |
Changes in aqueous solution (4)
- Reaction of ammonium thiocyanate and nitric acid
| 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 | −15.8 | – | – | – |
per 1 mol of | −15.8 | – | – | – |
per 1 mol of | −5.27 | – | – | – |
per 1 mol of | −7.90 | – | – | – |
per 1 mol of | −15.8 | – | – | – |
per 1 mol of | −15.8 | – | – | – |
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 |
|---|---|---|---|---|
| NH4SCN (cr) | -78.7[1] | – | – | – |
| NH4SCN (ai) | -56.07[1] | 13.40[1] | 257.7[1] | 39.7[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 |
|---|---|---|---|---|
| N2O3 (l) | 50.29[1] | – | – | – |
| N2O3 (g) | 83.72[1] | 139.46[1] | 312.28[1] | 65.61[1] |
| NH4HCO3 (cr) | -849.4[1] | -665.9[1] | 120.9[1] | – |
| NH4HCO3 (ai) | -824.50[1] | -666.07[1] | 204.6[1] | – |
| NH4HCO3 (aq) | -821.7[1] | – | – | – |
| H2S (g) | -20.63[1] | -33.56[1] | 205.79[1] | 34.23[1] |
| H2S (ao) | -39.7[1] | -27.83[1] | 121[1] | – |
* (l):Liquid, (g):Gas, (cr):Crystalline solid, (ai):Ionized aqueous solution, (aq):Aqueous solution, (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°, -78.7 kJ · mol−1
- ^ ΔfH°, -56.07 kJ · mol−1
- ^ ΔfG°, 13.40 kJ · mol−1
- ^ S°, 257.7 J · K−1 · mol−1
- ^ Cp°, 39.7 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°, 50.29 kJ · mol−1
- ^ ΔfH°, 83.72 kJ · mol−1
- ^ ΔfG°, 139.46 kJ · mol−1
- ^ S°, 312.28 J · K−1 · mol−1
- ^ Cp°, 65.61 J · K−1 · mol−1
- ^ ΔfH°, -849.4 kJ · mol−1
- ^ ΔfG°, -665.9 kJ · mol−1
- ^ S°, 120.9 J · K−1 · mol−1
- ^ ΔfH°, -824.50 kJ · mol−1
- ^ ΔfG°, -666.07 kJ · mol−1
- ^ S°, 204.6 J · K−1 · mol−1
- ^ ΔfH°, -821.7 kJ · mol−1
- ^ ΔfH°, -20.63 kJ · mol−1
- ^ ΔfG°, -33.56 kJ · mol−1
- ^ S°, 205.79 J · K−1 · mol−1
- ^ Cp°, 34.23 J · K−1 · mol−1
- ^ ΔfH°, -39.7 kJ · mol−1
- ^ ΔfG°, -27.83 kJ · mol−1
- ^ S°, 121. J · K−1 · mol−1