KSCN + 3HNO3 → KHCO3 + S + 2HNO2 + 2NO↑
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The reaction of potassium thiocyanate and nitric acid yields potassium hydrogencarbonate, , nitrous acid, and nitrogen monoxide (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 | 1 | Reducing | Reducing |
| HNO3 | Nitric acid | 3 | Oxidizing | Oxidizing |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| KHCO3 | Potassium hydrogencarbonate | 1 | – | – |
| 1 | Oxidized | – | ||
| HNO2 | Nitrous acid | 2 | Redoxed product | – |
| NO | Nitrogen monoxide | 2 | Reduced | – |
Thermodynamic changes
Changes in standard condition
- Reaction of potassium thiocyanate and nitric acid◆
ΔrG −273.8 kJ/mol K 9.28 × 1047 pK −47.97
| 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 | −204.3 | −273.8 | 232.1 | – |
per 1 mol of | −204.3 | −273.8 | 232.1 | – |
per 1 mol of | −68.10 | −91.27 | 77.37 | – |
per 1 mol of | −204.3 | −273.8 | 232.1 | – |
| −204.3 | −273.8 | 232.1 | – | |
per 1 mol of | −102.2 | −136.9 | 116.0 | – |
per 1 mol of | −102.2 | −136.9 | 116.0 | – |
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 |
|---|---|---|---|---|
| KHCO3 (cr) | -963.2[1] | -863.5[1] | 115.5[1] | – |
| KHCO3 (ai) | -944.37[1] | -870.04[1] | 193.7[1] | – |
| (cr) rhombic | 0[1] | 0[1] | 31.80[1] | 22.64[1] |
| (cr) monoclinic | 0.33[1] | – | – | – |
| (g) | 278.805[1] | 238.250[1] | 167.821[1] | 23.673[1] |
| HNO2 (g) cis | -77.99[1] | -42.94[1] | 248.76[1] | 44.77[1] |
| HNO2 (g) trans | -80.12[1] | -45.24[1] | 249.22[1] | 46.07[1] |
| HNO2 (g) | -79.5[1] | -46.0[1] | 254.1[1] | 45.6[1] |
| HNO2 (ao) | -119.2[1] | -50.6[1] | 135.6[1] | – |
| NO (g) | 90.25[1] | 86.55[1] | 210.761[1] | 29.844[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°, -963.2 kJ · mol−1
- ^ ΔfG°, -863.5 kJ · mol−1
- ^ S°, 115.5 J · K−1 · mol−1
- ^ ΔfH°, -944.37 kJ · mol−1
- ^ ΔfG°, -870.04 kJ · mol−1
- ^ S°, 193.7 J · K−1 · mol−1
- ^ ΔfH°, 0 kJ · mol−1
- ^ ΔfG°, 0 kJ · mol−1
- ^ S°, 31.80 J · K−1 · mol−1
- ^ Cp°, 22.64 J · K−1 · mol−1
- ^ ΔfH°, 0.33 kJ · mol−1
- ^ ΔfH°, 278.805 kJ · mol−1
- ^ ΔfG°, 238.250 kJ · mol−1
- ^ S°, 167.821 J · K−1 · mol−1
- ^ Cp°, 23.673 J · K−1 · mol−1
- ^ ΔfH°, -77.99 kJ · mol−1
- ^ ΔfG°, -42.94 kJ · mol−1
- ^ S°, 248.76 J · K−1 · mol−1
- ^ Cp°, 44.77 J · K−1 · mol−1
- ^ ΔfH°, -80.12 kJ · mol−1
- ^ ΔfG°, -45.24 kJ · mol−1
- ^ S°, 249.22 J · K−1 · mol−1
- ^ Cp°, 46.07 J · K−1 · mol−1
- ^ ΔfH°, -79.5 kJ · mol−1
- ^ ΔfG°, -46.0 kJ · mol−1
- ^ S°, 254.1 J · K−1 · mol−1
- ^ Cp°, 45.6 J · K−1 · mol−1
- ^ ΔfH°, -119.2 kJ · mol−1
- ^ ΔfG°, -50.6 kJ · mol−1
- ^ S°, 135.6 J · K−1 · mol−1
- ^ ΔfH°, 90.25 kJ · mol−1
- ^ ΔfG°, 86.55 kJ · mol−1
- ^ S°, 210.761 J · K−1 · mol−1
- ^ Cp°, 29.844 J · K−1 · mol−1