5HSCN + 6KOH → 2KHS + (NH4)2CO3 + KHCO3 + 3KSCN
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The reaction of thiocyanic acid and potassium hydroxide yields potassium hydrogensulfide, ammonium carbonate, potassium hydrogencarbonate, and potassium thiocyanate (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 thiocyanic acid and potassium hydroxide
General equation
- Reaction of acid and base
- AcidBrønsted acid + BaseBrønsted base ⟶ SaltConjugate base + (H2O)(Conjugate acid)
Oxidation state of each atom
- Reaction of thiocyanic acid and potassium hydroxide
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| HSCN | Thiocyanic acid | 5 | Brønsted acid | Acid |
| KOH | Potassium hydroxide | 6 | Brønsted base | Base |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| KHS | Potassium hydrogensulfide | 2 | Conjugate base | Salt |
| (NH4)2CO3 | Ammonium carbonate | 1 | Conjugate base | Salt |
| KHCO3 | Potassium hydrogencarbonate | 1 | Conjugate base | Salt |
| KSCN | Potassium thiocyanate | 3 | Conjugate base | Salt |
Thermodynamic changes
Changes in aqueous solution (1)
- Reaction of thiocyanic acid and potassium hydroxide◆
ΔrG −491.07 kJ/mol K 1.08 × 1086 pK −86.03
| 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 | −442.1 | −491.07 | 163.8 | – |
per 1 mol of | −88.42 | −98.214 | 32.76 | – |
per 1 mol of | −73.68 | −81.845 | 27.30 | – |
per 1 mol of | −221.1 | −245.53 | 81.90 | – |
per 1 mol of | −442.1 | −491.07 | 163.8 | – |
per 1 mol of | −442.1 | −491.07 | 163.8 | – |
per 1 mol of | −147.4 | −163.69 | 54.60 | – |
Changes in aqueous solution (2)
- Reaction of thiocyanic acid and potassium hydroxide◆
ΔrG −515.32 kJ/mol K 1.91 × 1090 pK −90.28
| 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 | – | −515.32 | – | – |
per 1 mol of | – | −103.06 | – | – |
per 1 mol of | – | −85.887 | – | – |
per 1 mol of | – | −257.66 | – | – |
per 1 mol of | – | −515.32 | – | – |
per 1 mol of | – | −515.32 | – | – |
per 1 mol of | – | −171.77 | – | – |
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 |
|---|---|---|---|---|
| HSCN (ai) | 76.44[1] | 92.71[1] | 144.3[1] | -40.2[1] |
| HSCN (ao) | – | 97.56[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] | – |
* (ai):Ionized aqueous solution, (ao):Un-ionized aqueous solution, (cr):Crystalline solid, (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 |
|---|---|---|---|---|
| KHS (cr) | -265.10[1] | – | – | 75.31[1] |
| KHS (ai) | -269.9[1] | -271.19[1] | 165.3[1] | – |
| KHS (cr) 0.25 hydrate | -337.2[1] | – | – | – |
| (NH4)2CO3 (ai) | -942.15[1] | -686.42[1] | 169.9[1] | – |
| KHCO3 (cr) | -963.2[1] | -863.5[1] | 115.5[1] | – |
| KHCO3 (ai) | -944.37[1] | -870.04[1] | 193.7[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] |
* (cr):Crystalline solid, (ai):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°, 76.44 kJ · mol−1
- ^ ΔfG°, 92.71 kJ · mol−1
- ^ S°, 144.3 J · K−1 · mol−1
- ^ Cp°, -40.2 J · K−1 · mol−1
- ^ ΔfG°, 97.56 kJ · 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°, -265.10 kJ · mol−1
- ^ Cp°, 75.31 J · K−1 · mol−1
- ^ ΔfH°, -269.9 kJ · mol−1
- ^ ΔfG°, -271.19 kJ · mol−1
- ^ S°, 165.3 J · K−1 · mol−1
- ^ ΔfH°, -337.2 kJ · mol−1
- ^ ΔfH°, -942.15 kJ · mol−1
- ^ ΔfG°, -686.42 kJ · mol−1
- ^ S°, 169.9 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°, -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