Ca(OH)2 + SO2 → CaSO3 + H2O
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The reaction of calcium hydroxide and sulfur dioxide yields calcium sulfite and water. This reaction is an acid-base reaction and is classified as follows:
- Reaction of base and acidic oxide
- Reaction of hydroxide base and acidic oxide
- Reaction of strong hydroxide base and weakly acidic oxide
Table of contents
Reaction data
Chemical equation
- Reaction of calcium hydroxide and sulfur dioxide
General equation
- Reaction of base and acidic oxide
- BaseLewis base + Acidic oxideLewis acid + H2O ⟶ Oxoacid saltLewis conjugate + (H2O)
- Reaction of hydroxide base and acidic oxide
- Hydroxide baseLewis base + Acidic oxideLewis acid ⟶ Oxoacid saltLewis conjugate + H2O
- Reaction of strong hydroxide base and weakly acidic oxide
- Strong hydroxide baseLewis base + Weakly acidic oxideLewis acid ⟶ Salt of weak acid and strong baseLewis conjugate + H2O
Oxidation state of each atom
- Reaction of calcium hydroxide and sulfur dioxide
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| Ca(OH)2 | Calcium hydroxide | 1 | Lewis base | Base Hydroxide base Strong hydroxide base |
| SO2 | Sulfur dioxide | 1 | Lewis acid | Acidic oxide Weakly acidic oxide |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| CaSO3 | Calcium sulfite | 1 | Lewis conjugate | Oxoacid salt Salt of weak acid and strong base |
| H2O | Water | 1 | – | Water |
Thermodynamic changes
Changes in standard condition
- Reaction of calcium hydroxide and sulfur dioxide
| 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 | – | – | −160.32 | 39.64 |
per 1 mol of | – | – | −160.32 | 39.64 |
per 1 mol of | – | – | −160.32 | 39.64 |
per 1 mol of | – | – | −160.32 | 39.64 |
per 1 mol of | – | – | −160.32 | 39.64 |
Changes in aqueous solution
- Reaction of calcium hydroxide and sulfur dioxide
| 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 | – | – | −74.0 | – |
per 1 mol of | – | – | −74.0 | – |
per 1 mol of | – | – | −74.0 | – |
per 1 mol of | – | – | −74.0 | – |
per 1 mol of | – | – | −74.0 | – |
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 |
|---|---|---|---|---|
| Ca(OH)2 (cr) | -986.09[1] | -898.49[1] | 83.39[1] | 87.49[1] |
| Ca(OH)2 (g) | -544[1] | – | – | – |
| Ca(OH)2 (ai) | -1002.82[1] | -868.07[1] | -74.5[1] | – |
| Ca(OH)2 (cr) 2 hydrate | -1218.4[1] | – | – | – |
| SO2 (l) | -320.5[1] | – | – | – |
| SO2 (g) | -296.830[1] | -300.194[1] | 248.22[1] | 39.87[1] |
| SO2 (ao) | -322.980[1] | -300.676[1] | 161.9[1] | – |
* (cr):Crystalline solid, (g):Gas, (ai):Ionized aqueous solution, (l):Liquid, (ao):Un-ionized 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 |
|---|---|---|---|---|
| CaSO3 (cr) | – | – | 101.38[1] | 91.71[1] |
| CaSO3 (cr) 0.5 hydrate | -1311.7[1] | -1199.23[1] | 121.3[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
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°, -986.09 kJ · mol−1
- ^ ΔfG°, -898.49 kJ · mol−1
- ^ S°, 83.39 J · K−1 · mol−1
- ^ Cp°, 87.49 J · K−1 · mol−1
- ^ ΔfH°, -544. kJ · mol−1
- ^ ΔfH°, -1002.82 kJ · mol−1
- ^ ΔfG°, -868.07 kJ · mol−1
- ^ S°, -74.5 J · K−1 · mol−1
- ^ ΔfH°, -1218.4 kJ · mol−1
- ^ ΔfH°, -320.5 kJ · mol−1
- ^ ΔfH°, -296.830 kJ · mol−1
- ^ ΔfG°, -300.194 kJ · mol−1
- ^ S°, 248.22 J · K−1 · mol−1
- ^ Cp°, 39.87 J · K−1 · mol−1
- ^ ΔfH°, -322.980 kJ · mol−1
- ^ ΔfG°, -300.676 kJ · mol−1
- ^ S°, 161.9 J · K−1 · mol−1
- ^ S°, 101.38 J · K−1 · mol−1
- ^ Cp°, 91.71 J · K−1 · mol−1
- ^ ΔfH°, -1311.7 kJ · mol−1
- ^ ΔfG°, -1199.23 kJ · mol−1
- ^ S°, 121.3 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