3KF + H3AsO4 🔥→ K3AsO4 + 3HF↑
Last updated:
- Reaction of potassium fluoride and arsenic acid
The reaction of potassium fluoride and arsenic acid yields potassium arsenate and hydrogen fluoride. This reaction is an acid-base reaction and is classified as follows:
Table of contents
Reaction data
Chemical equation
- Reaction of potassium fluoride and arsenic acid
General equation
- Salt of volatile acidBrønsted base + Nonvolatile acidBrønsted acid ⟶ Salt of non volatile acidConjugate base + Volatile acidConjugate acid
Oxidation state of each atom
- Reaction of potassium fluoride and arsenic acid
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| KF | Potassium fluoride | 3 | Brønsted base | Salt of volatile acid |
| H3AsO4 | Arsenic acid | 1 | Brønsted acid | Nonvolatile acid |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| K3AsO4 | Potassium arsenate | 1 | Conjugate base | Salt of non volatile acid |
| HF | Hydrogen fluoride | 3 | Conjugate acid | Volatile acid |
Thermodynamic changes
Changes in aqueous solution (1)
- Reaction of potassium fluoride and arsenic acid◆
ΔrG 134.4 kJ/mol K 0.28 × 10−23 pK 23.55
| 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 | 199.0 | 134.4 | 216 | – |
per 1 mol of | 66.33 | 44.80 | 72.0 | – |
per 1 mol of | 199.0 | 134.4 | 216 | – |
per 1 mol of | 199.0 | 134.4 | 216 | – |
per 1 mol of | 66.33 | 44.80 | 72.0 | – |
Changes in aqueous solution (2)
- Reaction of potassium fluoride and arsenic acid◆
ΔrG 63.5 kJ/mol K 0.75 × 10−11 pK 11.12
| 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 | 52.0 | 63.5 | −39 | – |
per 1 mol of | 17.3 | 21.2 | −13 | – |
per 1 mol of | 52.0 | 63.5 | −39 | – |
per 1 mol of | 52.0 | 63.5 | −39 | – |
per 1 mol of | 17.3 | 21.2 | −13 | – |
Changes in aqueous solution (3)
- Reaction of potassium fluoride and arsenic acid◆
ΔrG 63.5 kJ/mol K 0.75 × 10−11 pK 11.12
| 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 | 52.0 | 63.5 | −39 | – |
per 1 mol of | 17.3 | 21.2 | −13 | – |
per 1 mol of | 52.0 | 63.5 | −39 | – |
per 1 mol of | 52.0 | 63.5 | −39 | – |
per 1 mol of | 17.3 | 21.2 | −13 | – |
Changes in aqueous solution (4)
- Reaction of potassium fluoride and arsenic 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 | 201.1 | – | – | – |
per 1 mol of | 67.03 | – | – | – |
per 1 mol of | 201.1 | – | – | – |
per 1 mol of | 201.1 | – | – | – |
per 1 mol of | 67.03 | – | – | – |
Changes in aqueous solution (5)
- Reaction of potassium fluoride and arsenic 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 | 54.1 | – | – | – |
per 1 mol of | 18.0 | – | – | – |
per 1 mol of | 54.1 | – | – | – |
per 1 mol of | 54.1 | – | – | – |
per 1 mol of | 18.0 | – | – | – |
Changes in aqueous solution (6)
- Reaction of potassium fluoride and arsenic 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 | 54.1 | – | – | – |
per 1 mol of | 18.0 | – | – | – |
per 1 mol of | 54.1 | – | – | – |
per 1 mol of | 54.1 | – | – | – |
per 1 mol of | 18.0 | – | – | – |
Changes in aqueous solution (7)
- Reaction of potassium fluoride and arsenic acid◆
ΔrG 117.6 kJ/mol K 0.25 × 10−20 pK 20.60
| 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 | 14.4 | 117.6 | −347 | – |
per 1 mol of | 4.80 | 39.20 | −116 | – |
per 1 mol of | 14.4 | 117.6 | −347 | – |
per 1 mol of | 14.4 | 117.6 | −347 | – |
per 1 mol of | 4.80 | 39.20 | −116 | – |
Changes in aqueous solution (8)
- Reaction of potassium fluoride and arsenic 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 | 16.5 | – | – | – |
per 1 mol of | 5.50 | – | – | – |
per 1 mol of | 16.5 | – | – | – |
per 1 mol of | 16.5 | – | – | – |
per 1 mol of | 5.50 | – | – | – |
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 |
|---|---|---|---|---|
| KF (cr) | -567.27[1] | -537.75[1] | 66.57[1] | 49.04[1] |
| KF (g) | -325.43[1] | -343.62[1] | 226.41[1] | 35.23[1] |
| KF (ai) | -585.01[1] | -562.06[1] | 88.7[1] | -84.9[1] |
| KF (cr) 2 hydrate | -1163.621[1] | -1021.49[1] | 155.2[1] | – |
| H3AsO4 (cr) | -906.3[1] | – | – | – |
| H3AsO4 (ao) | -902.5[1] | -766.0[1] | 184[1] | – |
| H3AsO4 (aq) | -904.6[1] | – | – | – |
* (cr):Crystalline solid, (g):Gas, (ai):Ionized aqueous solution, (ao):Un-ionized aqueous solution, (aq):Aqueous solution
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 |
|---|---|---|---|---|
| K3AsO4 (ai) | -1645.27[1] | -1498.23[1] | 144.8[1] | – |
| HF (l) x denotes undetermined zero point entropy | -299.78[1] | – | 75.40+x[1] | – |
| HF (g) | -271.1[1] | -273.2[1] | 173.779[1] | 29.133[1] |
| HF (ai) | -332.63[1] | -278.79[1] | -13.8[1] | -106.7[1] |
| HF (ao) | -320.08[1] | -296.82[1] | 88.7[1] | – |
* (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°, -567.27 kJ · mol−1
- ^ ΔfG°, -537.75 kJ · mol−1
- ^ S°, 66.57 J · K−1 · mol−1
- ^ Cp°, 49.04 J · K−1 · mol−1
- ^ ΔfH°, -325.43 kJ · mol−1
- ^ ΔfG°, -343.62 kJ · mol−1
- ^ S°, 226.41 J · K−1 · mol−1
- ^ Cp°, 35.23 J · K−1 · mol−1
- ^ ΔfH°, -585.01 kJ · mol−1
- ^ ΔfG°, -562.06 kJ · mol−1
- ^ S°, 88.7 J · K−1 · mol−1
- ^ Cp°, -84.9 J · K−1 · mol−1
- ^ ΔfH°, -1163.621 kJ · mol−1
- ^ ΔfG°, -1021.49 kJ · mol−1
- ^ S°, 155.2 J · K−1 · mol−1
- ^ ΔfH°, -906.3 kJ · mol−1
- ^ ΔfH°, -902.5 kJ · mol−1
- ^ ΔfG°, -766.0 kJ · mol−1
- ^ S°, 184. J · K−1 · mol−1
- ^ ΔfH°, -904.6 kJ · mol−1
- ^ ΔfH°, -1645.27 kJ · mol−1
- ^ ΔfG°, -1498.23 kJ · mol−1
- ^ S°, 144.8 J · K−1 · mol−1
- ^ ΔfH°, -299.78 kJ · mol−1
- ^ S°, 75.40+x J · K−1 · mol−1
- ^ ΔfH°, -271.1 kJ · mol−1
- ^ ΔfG°, -273.2 kJ · mol−1
- ^ S°, 173.779 J · K−1 · mol−1
- ^ Cp°, 29.133 J · K−1 · mol−1
- ^ ΔfH°, -332.63 kJ · mol−1
- ^ ΔfG°, -278.79 kJ · mol−1
- ^ S°, -13.8 J · K−1 · mol−1
- ^ Cp°, -106.7 J · K−1 · mol−1
- ^ ΔfH°, -320.08 kJ · mol−1
- ^ ΔfG°, -296.82 kJ · mol−1
- ^ S°, 88.7 J · K−1 · mol−1