Formula Al(NO3)3 IUPAC ID Aluminium nitrate Density 1.72 g/cm³ Soluble in Water | Molar mass 212.996 g/mol Melting point 72.8 °C Boiling point 135 °C | |
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Appearance White crystals, solidhygroscopic | ||
Aluminium nitrate is a white, water-soluble salt of aluminium and nitric acid, most commonly existing as the crystalline hydrate, aluminium nitrate nonahydrate, Al(NO3)3·9H2O.
Contents
Preparation
Aluminium nitrate cannot be synthesized by the reaction of aluminium with concentrated nitric acid, as the aluminium forms a passivation layer.
Aluminium nitrate may instead be prepared by the reaction of nitric acid with aluminium(III) chloride. Nitrosyl chloride is produced as a by-product; it bubbles out of the solution as a gas.
Aluminium nitrate may also be prepared a metathesis reaction between aluminium sulfate and a nitrate salt with a suitable cation such as barium, strontium, calcium, silver, or lead. e.g. Al2(SO4)3 + 3Ba(NO3)2 → 2Al(NO3)3 + 3BaSO4
Uses
Aluminium nitrate is a strong oxidizing agent. It is used in tanning leather, antiperspirants, corrosion inhibitors, extraction of uranium, petroleum refining, and as a nitrating agent.
The nonahydrate and other hydrated aluminium nitrates have many applications. These salts are used to produce alumina for preparation of insulating papers, in cathode ray tube heating elements, and on transformer core laminates. The hydrated salts are also used for the extraction of actinide elements.
It is used in the laboratory and classroom such as in the reaction:
Al(NO3)3 + 3 NaOH → Al(OH)3 + 3 NaNO3