HCN + KOH → KCN + H2O
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The reaction of hydrogen cyanide and potassium hydroxide yields potassium cyanide and water. This reaction is an acid-base reaction and is classified as follows:
Table of contents
Reaction data
Chemical equation
- Reaction of hydrogen cyanide and potassium hydroxide
General equation
- Reaction of acid and base
- AcidBrønsted acid + BaseBrønsted base ⟶ SaltConjugate base + (H2O)(Conjugate acid)
- Reaction of acid and hydroxide base
- AcidBrønsted acid + Hydroxide baseBrønsted base ⟶ SaltConjugate base + H2OConjugate acid
- Reaction of weak acid and strong base
- Weak acidBrønsted acid + Strong baseBrønsted base ⟶ Salt of weak acid and strong baseConjugate base + (H2O)(Conjugate acid)
Oxidation state of each atom
- Reaction of hydrogen cyanide and potassium hydroxide
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| HCN | Hydrogen cyanide | 1 | Brønsted acid | Acid Weak acid |
| KOH | Potassium hydroxide | 1 | Brønsted base | Base Hydroxide base Strong base |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| KCN | Potassium cyanide | 1 | Conjugate base | Salt Salt of weak acid and strong base |
| H2O | Water | 1 | Conjugate acid | Water |
Thermodynamic changes
Changes in standard condition
- Reaction of hydrogen cyanide and potassium hydroxide◆
ΔrG −84.88 kJ/mol K 7.42 × 1014 pK −14.87
| 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 | −82.9 | −84.88 | 6.7 | 6.0 |
per 1 mol of | −82.9 | −84.88 | 6.7 | 6.0 |
per 1 mol of | −82.9 | −84.88 | 6.7 | 6.0 |
per 1 mol of | −82.9 | −84.88 | 6.7 | 6.0 |
per 1 mol of | −82.9 | −84.88 | 6.7 | 6.0 |
Changes in aqueous solution (1)
- Reaction of hydrogen cyanide and potassium hydroxide◆
ΔrG −79.9 kJ/mol K 9.95 × 1013 pK −14.00
| 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 | −55.8 | −79.9 | 80.8 | – |
per 1 mol of | −55.8 | −79.9 | 80.8 | – |
per 1 mol of | −55.8 | −79.9 | 80.8 | – |
per 1 mol of | −55.8 | −79.9 | 80.8 | – |
per 1 mol of | −55.8 | −79.9 | 80.8 | – |
Changes in aqueous solution (2)
- Reaction of hydrogen cyanide and potassium hydroxide◆
ΔrG −27.2 kJ/mol K 5.82 × 104 pK −4.77
| 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 | −12.3 | −27.2 | 50.2 | – |
per 1 mol of | −12.3 | −27.2 | 50.2 | – |
per 1 mol of | −12.3 | −27.2 | 50.2 | – |
per 1 mol of | −12.3 | −27.2 | 50.2 | – |
per 1 mol of | −12.3 | −27.2 | 50.2 | – |
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 |
|---|---|---|---|---|
| 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] | – |
| KOH (cr) | -424.764[1] | -379.08[1] | 78.9[1] | 64.9[1] |
| KOH (g) | -231.0[1] | -232.6[1] | 238.3[1] | 49.20[1] |
| KOH (ai) | -482.37[1] | -440.50[1] | 91.6[1] | -126.8[1] |
| KOH (cr) 1 hydrate | -748.9[1] | -645.1[1] | 117.2[1] | – |
| KOH (cr) 2 hydrate | -1051.0[1] | -887.3[1] | 150.6[1] | – |
* (l):Liquid, (g):Gas, (ai):Ionized aqueous solution, (ao):Un-ionized aqueous solution, (cr):Crystalline solid
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 |
|---|---|---|---|---|
| KCN (cr) | -113.0[1] | -101.86[1] | 128.49[1] | 66.27[1] |
| KCN (g) | 90.8[1] | 64.17[1] | 261.90[1] | 52.34[1] |
| KCN (ai) | -101.7[1] | -110.9[1] | 196.6[1] | – |
| H2O (cr) | – | – | – | – |
| H2O (l) | -285.830[1] | -237.129[1] | 69.91[1] | 75.291[1] |
| H2O (g) | -241.818[1] | -228.572[1] | 188.825[1] | 33.577[1] |
* (cr):Crystalline solid, (g):Gas, (ai):Ionized aqueous solution, (l):Liquid
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°, 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
- ^ ΔfH°, -424.764 kJ · mol−1
- ^ ΔfG°, -379.08 kJ · mol−1
- ^ S°, 78.9 J · K−1 · mol−1
- ^ Cp°, 64.9 J · K−1 · mol−1
- ^ ΔfH°, -231.0 kJ · mol−1
- ^ ΔfG°, -232.6 kJ · mol−1
- ^ S°, 238.3 J · K−1 · mol−1
- ^ Cp°, 49.20 J · K−1 · mol−1
- ^ ΔfH°, -482.37 kJ · mol−1
- ^ ΔfG°, -440.50 kJ · mol−1
- ^ S°, 91.6 J · K−1 · mol−1
- ^ Cp°, -126.8 J · K−1 · mol−1
- ^ ΔfH°, -748.9 kJ · mol−1
- ^ ΔfG°, -645.1 kJ · mol−1
- ^ S°, 117.2 J · K−1 · mol−1
- ^ ΔfH°, -1051.0 kJ · mol−1
- ^ ΔfG°, -887.3 kJ · mol−1
- ^ S°, 150.6 J · K−1 · mol−1
- ^ ΔfH°, -113.0 kJ · mol−1
- ^ ΔfG°, -101.86 kJ · mol−1
- ^ S°, 128.49 J · K−1 · mol−1
- ^ Cp°, 66.27 J · K−1 · mol−1
- ^ ΔfH°, 90.8 kJ · mol−1
- ^ ΔfG°, 64.17 kJ · mol−1
- ^ S°, 261.90 J · K−1 · mol−1
- ^ Cp°, 52.34 J · K−1 · mol−1
- ^ ΔfH°, -101.7 kJ · mol−1
- ^ ΔfG°, -110.9 kJ · mol−1
- ^ S°, 196.6 J · K−1 · mol−1
- ^ ΔfH°, -285.830 kJ · mol−1
- ^ ΔfG°, -237.129 kJ · mol−1
- ^ S°, 69.91 J · K−1 · mol−1
- ^ Cp°, 75.291 J · K−1 · mol−1
- ^ ΔfH°, -241.818 kJ · mol−1
- ^ ΔfG°, -228.572 kJ · mol−1
- ^ S°, 188.825 J · K−1 · mol−1
- ^ Cp°, 33.577 J · K−1 · mol−1