2NH4CN + H2SO4 → (NH4)2SO4 + 2HCN
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The reaction of ammonium cyanide and sulfuric acid yields ammonium sulfate and hydrogen cyanide (Other reactions are here). This reaction is an acid-base reaction and is classified as follows:
Table of contents
Reaction data
Chemical equation
- Reaction of ammonium cyanide and sulfuric acid
General equation
- Salt of weak acidBrønsted base + Strong acidBrønsted acid ⟶ Salt of strong acidConjugate base + Weak acidConjugate acid
- Salt of volatile acidBrønsted base + Nonvolatile acidBrønsted acid ⟶ Salt of non volatile acidConjugate base + Volatile acidConjugate acid
Oxidation state of each atom
- Reaction of ammonium cyanide and sulfuric acid
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| NH4CN | Ammonium cyanide | 2 | Brønsted base | Salt of weak acid Salt of volatile acid |
| H2SO4 | Sulfuric acid | 1 | Brønsted acid | Strong acid Nonvolatile acid |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| (NH4)2SO4 | Ammonium sulfate | 1 | Conjugate base | Salt of strong acid Salt of non volatile acid |
| HCN | Hydrogen cyanide | 2 | Conjugate acid | Weak acid Volatile acid |
Thermodynamic changes
Changes in standard condition
- Reaction of ammonium cyanide and sulfuric 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 | −149.96 | – | – | −78 |
per 1 mol of | −74.980 | – | – | −39 |
per 1 mol of | −149.96 | – | – | −78 |
per 1 mol of | −149.96 | – | – | −78 |
per 1 mol of | −74.980 | – | – | −39 |
Changes in aqueous solution (1)
- Reaction of ammonium cyanide and sulfuric acid◆
ΔrG −105.2 kJ/mol K 2.69 × 1018 pK −18.43
| 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 | −86.8 | −105.2 | 61.2 | – |
per 1 mol of | −43.4 | −52.60 | 30.6 | – |
per 1 mol of | −86.8 | −105.2 | 61.2 | – |
per 1 mol of | −86.8 | −105.2 | 61.2 | – |
per 1 mol of | −43.4 | −52.60 | 30.6 | – |
Changes in aqueous solution (2)
- Reaction of ammonium cyanide and sulfuric 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 | −115.2 | – | – | – |
per 1 mol of | −57.60 | – | – | – |
per 1 mol of | −115.2 | – | – | – |
per 1 mol of | −115.2 | – | – | – |
per 1 mol of | −57.60 | – | – | – |
Changes in aqueous solution (3)
- Reaction of ammonium cyanide and sulfuric acid◆
ΔrG 0.2 kJ/mol K 0.92 × 100 pK 0.04
| 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 | 0.2 | 0.2 | 0.0 | – |
per 1 mol of | 0.10 | 0.10 | 0.0 | – |
per 1 mol of | 0.20 | 0.20 | 0.0 | – |
per 1 mol of | 0.20 | 0.20 | 0.0 | – |
per 1 mol of | 0.10 | 0.10 | 0.0 | – |
Changes in aqueous solution (4)
- Reaction of ammonium cyanide and sulfuric 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 | −28.2 | – | – | – |
per 1 mol of | −14.1 | – | – | – |
per 1 mol of | −28.2 | – | – | – |
per 1 mol of | −28.2 | – | – | – |
per 1 mol of | −14.1 | – | – | – |
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 |
|---|---|---|---|---|
| NH4CN (cr) | 0.42[1] | – | – | 134[1] |
| NH4CN (ai) | 18.0[1] | 93.0[1] | 207.5[1] | – |
| NH4CN (aq) | 32.2[1] | – | – | – |
| H2SO4 (cr) | – | – | – | – |
| H2SO4 (l) | -813.989[1] | -690.003[1] | 156.904[1] | 138.91[1] |
| H2SO4 (ai) | -909.27[1] | -744.53[1] | 20.1[1] | -293[1] |
| H2SO4 (l) 1 hydrate | -1127.621[1] | -950.383[1] | 211.54[1] | 214.85[1] |
| H2SO4 (l) 2 hydrate | -1427.100[1] | -1199.650[1] | 276.40[1] | 260.83[1] |
| H2SO4 (l) 3 hydrate | -1720.402[1] | -1443.980[1] | 345.39[1] | 318.95[1] |
| H2SO4 (l) 4 hydrate | -2011.199[1] | -1685.863[1] | 414.59[1] | 382.21[1] |
| H2SO4 (l) 6.5 hydrate | -2733.256[1] | -2285.734[1] | 587.89[1] | 570.28[1] |
* (cr):Crystalline solid, (ai):Ionized aqueous solution, (aq):Aqueous solution, (l):Liquid
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 |
|---|---|---|---|---|
| (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] |
| HCN (l) | 108.87[1] | 124.97[1] | 112.84[1] | 70.63[1] |
| HCN (g) | 135.1[1] | 124.7[1] | 201.78[1] | 35.86[1] |
| HCN (ai) | 150.6[1] | 172.4[1] | 94.1[1] | – |
| HCN (ao) | 107.1[1] | 119.7[1] | 124.7[1] | – |
* (cr):Crystalline solid, (ai):Ionized aqueous solution, (l):Liquid, (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°, 0.42 kJ · mol−1
- ^ Cp°, 134. J · K−1 · mol−1
- ^ ΔfH°, 18.0 kJ · mol−1
- ^ ΔfG°, 93.0 kJ · mol−1
- ^ S°, 207.5 J · K−1 · mol−1
- ^ ΔfH°, 32.2 kJ · mol−1
- ^ ΔfH°, -813.989 kJ · mol−1
- ^ ΔfG°, -690.003 kJ · mol−1
- ^ S°, 156.904 J · K−1 · mol−1
- ^ Cp°, 138.91 J · K−1 · mol−1
- ^ ΔfH°, -909.27 kJ · mol−1
- ^ ΔfG°, -744.53 kJ · mol−1
- ^ S°, 20.1 J · K−1 · mol−1
- ^ Cp°, -293. J · K−1 · mol−1
- ^ ΔfH°, -1127.621 kJ · mol−1
- ^ ΔfG°, -950.383 kJ · mol−1
- ^ S°, 211.54 J · K−1 · mol−1
- ^ Cp°, 214.85 J · K−1 · mol−1
- ^ ΔfH°, -1427.100 kJ · mol−1
- ^ ΔfG°, -1199.650 kJ · mol−1
- ^ S°, 276.40 J · K−1 · mol−1
- ^ Cp°, 260.83 J · K−1 · mol−1
- ^ ΔfH°, -1720.402 kJ · mol−1
- ^ ΔfG°, -1443.980 kJ · mol−1
- ^ S°, 345.39 J · K−1 · mol−1
- ^ Cp°, 318.95 J · K−1 · mol−1
- ^ ΔfH°, -2011.199 kJ · mol−1
- ^ ΔfG°, -1685.863 kJ · mol−1
- ^ S°, 414.59 J · K−1 · mol−1
- ^ Cp°, 382.21 J · K−1 · mol−1
- ^ ΔfH°, -2733.256 kJ · mol−1
- ^ ΔfG°, -2285.734 kJ · mol−1
- ^ S°, 587.89 J · K−1 · mol−1
- ^ Cp°, 570.28 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°, 108.87 kJ · mol−1
- ^ ΔfG°, 124.97 kJ · mol−1
- ^ S°, 112.84 J · K−1 · mol−1
- ^ Cp°, 70.63 J · K−1 · mol−1
- ^ ΔfH°, 135.1 kJ · mol−1
- ^ ΔfG°, 124.7 kJ · mol−1
- ^ S°, 201.78 J · K−1 · mol−1
- ^ Cp°, 35.86 J · K−1 · mol−1
- ^ ΔfH°, 150.6 kJ · mol−1
- ^ ΔfG°, 172.4 kJ · mol−1
- ^ S°, 94.1 J · K−1 · mol−1
- ^ ΔfH°, 107.1 kJ · mol−1
- ^ ΔfG°, 119.7 kJ · mol−1
- ^ S°, 124.7 J · K−1 · mol−1