NH4SCN + 4HNO3 → 2N2O3↑ + (NH4)2SO4 + CO2↑
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The reaction of ammonium thiocyanate and nitric acid yields dinitrogen trioxide, ammonium sulfate, 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 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 | 4 | Oxidizing | Oxidizing |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| N2O3 | Dinitrogen trioxide | 2 | Reduced | – |
| (NH4)2SO4 | Ammonium sulfate | 1 | Oxidized | – |
| CO2 | Carbon dioxide | 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 | −631.8 | – | – | – |
per 1 mol of | −631.8 | – | – | – |
per 1 mol of | −157.9 | – | – | – |
per 1 mol of | −315.9 | – | – | – |
per 1 mol of | −631.8 | – | – | – |
per 1 mol of | −631.8 | – | – | – |
Changes in aqueous solution (1)
- Reaction of ammonium thiocyanate and nitric acid◆
ΔrG −586.98 kJ/mol K 6.83 × 10102 pK −102.83
| 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 | −514.84 | −586.98 | 241.9 | 341.9 |
per 1 mol of | −514.84 | −586.98 | 241.9 | 341.9 |
per 1 mol of | −128.71 | −146.75 | 60.48 | 85.47 |
per 1 mol of | −257.42 | −293.49 | 121.0 | 170.9 |
per 1 mol of | −514.84 | −586.98 | 241.9 | 341.9 |
per 1 mol of | −514.84 | −586.98 | 241.9 | 341.9 |
Changes in aqueous solution (2)
- Reaction of ammonium thiocyanate and nitric acid◆
ΔrG −578.60 kJ/mol K 2.32 × 10101 pK −101.37
| 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 | −535.13 | −578.60 | 145.8 | – |
per 1 mol of | −535.13 | −578.60 | 145.8 | – |
per 1 mol of | −133.78 | −144.65 | 36.45 | – |
per 1 mol of | −267.56 | −289.30 | 72.90 | – |
per 1 mol of | −535.13 | −578.60 | 145.8 | – |
per 1 mol of | −535.13 | −578.60 | 145.8 | – |
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] |
| (NH4)2SO4 (cr) | -1180.85[1] | -901.67[1] | 220.1[1] | 187.49[1] |
| (NH4)2SO4 (ai) | -1174.28[1] | -903.14[1] | 246.9[1] | -133.1[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] | – |
* (l):Liquid, (g):Gas, (cr):Crystalline solid, (ai):Ionized 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°, -1180.85 kJ · mol−1
- ^ ΔfG°, -901.67 kJ · mol−1
- ^ S°, 220.1 J · K−1 · mol−1
- ^ Cp°, 187.49 J · K−1 · mol−1
- ^ ΔfH°, -1174.28 kJ · mol−1
- ^ ΔfG°, -903.14 kJ · mol−1
- ^ S°, 246.9 J · K−1 · mol−1
- ^ Cp°, -133.1 J · K−1 · 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