PbS + 2H2O → Pb(OH)2 + H2S↑
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- Hydrolysis of lead(II) sulfide
The reaction of lead(II) sulfide and water yields lead(II) hydroxide and hydrogen sulfide. This reaction is an acid-base reaction and is classified as follows:
Table of contents
Reaction data
Chemical equation
- Hydrolysis of lead(II) sulfide
General equation
- Hydrolysis of salt
- Salt of weak acid and weak baseBrønsted base + H2OBrønsted acid ⟶ Base/Basic saltConjugate base + Acid/Acid salt/HydrideConjugate acid
Oxidation state of each atom
- Hydrolysis of lead(II) sulfide
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| PbS | Lead(II) sulfide | 1 | Brønsted base | Salt of weak acid and weak base |
| H2O | Water | 2 | Brønsted acid | Water |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| Pb(OH)2 | Lead(II) hydroxide | 1 | Conjugate base | Base |
| H2S | Hydrogen sulfide | 1 | Conjugate acid | Acid |
Thermodynamic changes
Changes in standard condition (1)
- Hydrolysis of lead(II) sulfide◆
ΔrG 87.2 kJ/mol K 0.53 × 10−15 pK 15.28
| 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 | – | 87.2 | – | – |
per 1 mol of | – | 87.2 | – | – |
per 1 mol of | – | 43.6 | – | – |
per 1 mol of | – | 87.2 | – | – |
per 1 mol of | – | 87.2 | – | – |
Changes in standard condition (2)
- Hydrolysis of lead(II) sulfide
| 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 | 135.5 | – | – | – |
per 1 mol of | 135.5 | – | – | – |
per 1 mol of | 67.75 | – | – | – |
per 1 mol of | 135.5 | – | – | – |
per 1 mol of | 135.5 | – | – | – |
Changes in aqueous solution (1)
- Hydrolysis of lead(II) sulfide◆
ΔrG 87.2 kJ/mol K 0.53 × 10−15 pK 15.28
| 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 | – | 87.2 | – | – |
per 1 mol of | – | 87.2 | – | – |
per 1 mol of | – | 43.6 | – | – |
per 1 mol of | – | 87.2 | – | – |
per 1 mol of | – | 87.2 | – | – |
Changes in aqueous solution (2)
- Hydrolysis of lead(II) sulfide◆
ΔrG 92.9 kJ/mol K 0.53 × 10−16 pK 16.28
| 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 | – | 92.9 | – | – |
per 1 mol of | – | 92.9 | – | – |
per 1 mol of | – | 46.5 | – | – |
per 1 mol of | – | 92.9 | – | – |
per 1 mol of | – | 92.9 | – | – |
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 |
|---|---|---|---|---|
| PbS (cr) | -100.4[1] | -98.7[1] | 91.2[1] | 49.50[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, (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 |
|---|---|---|---|---|
| Pb(OH)2 (cr) | – | -452.2[1] | – | – |
| Pb(OH)2 (cr) precipitated | -515.9[1] | – | – | – |
| H2S (g) | -20.63[1] | -33.56[1] | 205.79[1] | 34.23[1] |
| H2S (ao) | -39.7[1] | -27.83[1] | 121[1] | – |
* (cr):Crystalline solid, (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°, -100.4 kJ · mol−1
- ^ ΔfG°, -98.7 kJ · mol−1
- ^ S°, 91.2 J · K−1 · mol−1
- ^ Cp°, 49.50 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
- ^ ΔfG°, -452.2 kJ · mol−1
- ^ ΔfH°, -515.9 kJ · mol−1
- ^ ΔfH°, -20.63 kJ · mol−1
- ^ ΔfG°, -33.56 kJ · mol−1
- ^ S°, 205.79 J · K−1 · mol−1
- ^ Cp°, 34.23 J · K−1 · mol−1
- ^ ΔfH°, -39.7 kJ · mol−1
- ^ ΔfG°, -27.83 kJ · mol−1
- ^ S°, 121. J · K−1 · mol−1