SiO32− + 3H2O → H4SiO4 + 2OH−
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The reaction of metasilicate ion and water yields silicic acid and hydroxide ion (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 metasilicate ion and water
General equation
- Cation/AnionBrønsted base + H2OBrønsted acid ⟶ Proton donating ion/AcidConjugate acid + OH−Conjugate base
Oxidation state of each atom
- Reaction of metasilicate ion and water
Reactants
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| SiO32− | Metasilicate ion | 1 | Brønsted base | Anion |
| H2O | Water | 3 | Brønsted acid | Water |
Products
| Chemical formula | Name | Coefficient | Type | Type in general equation |
|---|---|---|---|---|
| H4SiO4 | Silicic acid | 1 | Conjugate acid | Acid |
| OH− | Hydroxide ion | 2 | Conjugate base | Hydroxide ion |
Thermodynamic changes
Changes in standard condition
| 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 | 33.5 | 20.1 | 45 | – |
per 1 mol of Metasilicate ion | 33.5 | 20.1 | 45 | – |
per 1 mol of | 11.2 | 6.70 | 15 | – |
per 1 mol of Silicic acid | 33.5 | 20.1 | 45 | – |
per 1 mol of Hydroxide ion | 16.8 | 10.1 | 23 | – |
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 |
|---|---|---|---|---|
| SiO32− (ao) | -1104.576[1] | -939.764[1] | -96.232[1] | – |
| H2O (cr) | – | – | – | – |
| H2O (l) | -285.830[2] | -237.129[2] | 69.91[2] | 75.291[2] |
| H2O (g) | -241.818[2] | -228.572[2] | 188.825[2] | 33.577[2] |
* (ao):Un-ionized aqueous solution, (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 |
|---|---|---|---|---|
| H4SiO4 (cr) | -1481.1[2] | -1332.9[2] | 192[2] | – |
| H4SiO4 (ao) | -1468.6[2] | -1316.6[2] | 180[2] | – |
| OH− (g) | -143.5[2] | – | – | – |
| OH− (ao) | -229.994[2] | -157.244[2] | -10.75[2] | -148.5[2] |
* (cr):Crystalline solid, (ao):Un-ionized aqueous solution, (g):Gas
References
List of references
- 1Colin Stuart Walker, Anraku Sohtaro, Oda Chie, Mitsui Seiichiro, Mihara MorihiroThermodynamic properties of SiO2(aq), HSiO3– and SiO3-2Japan Atomic Energy Agency
- 2Janiel 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°, -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
- ^ ΔfH°, -1481.1 kJ · mol−1
- ^ ΔfG°, -1332.9 kJ · mol−1
- ^ S°, 192. J · K−1 · mol−1
- ^ ΔfH°, -1468.6 kJ · mol−1
- ^ ΔfG°, -1316.6 kJ · mol−1
- ^ S°, 180. J · K−1 · mol−1
- ^ ΔfH°, -143.5 kJ · mol−1
- ^ ΔfH°, -229.994 kJ · mol−1
- ^ ΔfG°, -157.244 kJ · mol−1
- ^ S°, -10.75 J · K−1 · mol−1
- ^ Cp°, -148.5 J · K−1 · mol−1