Sodium aluminate
| Crystal structure with sodium in yellow, aluminium in grey, and oxygen in red | |
| Sodium metaaluminate sample | |
| Names | |
|---|---|
| IUPAC name Sodium aluminate | |
| Other names Sodium aluminium oxide, Sodium metaaluminate Aluminate, ((AlO2)1−), sodium | |
| Identifiers | |
| 3D model (JSmol) | |
| ECHA InfoCard | 100.013.728 | 
| EC Number | 
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| PubChem CID | |
| UNII | |
| CompTox Dashboard (EPA) | |
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| Properties | |
| NaAlO2 | |
| Molar mass | 81.97 g/mol | 
| Appearance | white powder (sometimes light-yellowish) hygroscopic/ when dissolved in water a colloidal black solution is formed | 
| Odor | odorless | 
| Density | 1.5 g/cm3 | 
| Melting point | 1,650 °C (3,000 °F; 1,920 K) | 
| highly soluble | |
| Solubility | Insoluble in alcohol | 
| Refractive index (nD) | 1.566 | 
| Structure | |
| orthorhombic | |
| Thermochemistry | |
| Heat capacity (C) | 73.6 J/mol K | 
| Std molar entropy (S⦵298) | 70.4 J/mol K | 
| Std enthalpy of formation (ΔfH⦵298) | −1133.2 kJ/mol | 
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references | |
Sodium aluminate is an inorganic chemical that is used as an effective source of aluminium hydroxide for many industrial and technical applications. Pure sodium aluminate (anhydrous) is a white crystalline solid having a formula variously given as NaAlO2, NaAl(OH)4 (hydrated), Na2O·Al2O3, or Na2Al2O4. Commercial sodium aluminate is available as a solution or a solid.
Other related compounds, sometimes called sodium aluminate, prepared by reaction of Na2O and Al2O3 are Na5AlO4 which contains discrete AlO45− anions, Na7Al3O8 and Na17Al5O16 which contain complex polymeric anions, and NaAl11O17, once mistakenly believed to be β-alumina, a phase of aluminium oxide.