Aluminium nitrate nonahydrate sample
| IUPAC name
| Preferred IUPAC name
| Other names
Nitric acid, aluminum salt
| Al(NO3)3 (anhydrous)|
|Molar mass|| 212.996 g/mol (anhydrous)|
375.134 g/mol (nonahydrate)
|Appearance||White hygroscopic crystals|
|Odor|| Odorless (fresh)|
Slightly pungent (old)
|Density||1.72 g/cm3 (nonahydrate)|
|Melting point|| 66 °C (151 °F; 339 K) (anhydrous)|
73.9 °C (165.0 °F; 347.0 K) (nonahydrate)
|Boiling point||150 °C (302 °F; 423 K) (nonahydrate); decomposes|
60.0 g/100 ml (0 °C)
73.9 g/100 ml (20 °C)
160 g/100 ml (100 °C)
67.3 g/100 ml
|Solubility||Insoluble in chloroform, dichloromethane, toluene, xylene|
|Solubility in methanol||14.45 g/100 ml|
|Solubility in ethanol||8.63 g/100 ml|
|Solubility in ethylene glycol||18.32 g/100 ml|
|Safety data sheet||Sigma-Aldrich|
|Flash point||35 °C (95 °F; 308 K) (nonahydrate)|
|Lethal dose or concentration (LD, LC):|
LD50 (Median dose)
|4,280 mg/kg (oral, rat)|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Aluminium nitrate reacts with sodium hydroxide, precipitating aluminium hydroxide:
- Al(NO3)3 + 3 NaOH → Al(OH)3 + 3 NaNO3
- 2 Al(NO3)3 → Al2O3 + 6 NO2 + 3/2 O2
Aluminium nitrate is an odorless, white crystalline hygroscopic salt. It has good solubility in water (73.9 g/100 ml at 20 °C), but is less soluble in alcohols and ethylene glycol. It melts at 66 °C (anhydrous) and 73.9 °C (nonahydrate), and if heated higher the nonahydrate will decompose.
Aluminium nitrate is sold by chemical suppliers. It can sometimes be found on eBay.
Aluminium nitrate cannot be made by adding aluminium to nitric acid, as the aluminium forms a passivation layer which prevents the reaction from taking place. One way around it is to add nitric acid to another compound of aluminium, such as aluminium chloride, reaction which gives off nitrosyl chloride fumes.
If you want to avoid the fumes, use aluminium hydroxide as a precursor chemical, which can be obtained by adding a soluble hydroxide to an aluminium salt. This reaction however will yield the hydrated form.
Obtaining anhydrous aluminium nitrate is difficult, as it tends to decompose when heated, making it a poor choice for oxidizer in pyrotechnic mixtures.
- Make alumina nanoparticles
- Pyrotechnic mixtures (complicated)
- Make nitrogen dioxide
- Compound collecting
Aluminium compounds are toxic and should be handled with care. Thermal decomposition of aluminium nitrate yields nitrogen dioxide which is corrosive and very toxic.
The anhydrous form must be stored in good airtight containers, while the nonahydrate should be stored away from moisture, in airtight bottles. Aluminium nitrate nonahydrate samples will take on a slight yellowish tint after several years of contact with air.
Adding sodium hydroxide or any other base will neutralize the compound to aluminium hydroxide, which is easier to take care of.