Aluminium Hydrocarbon

Aluminium methyl, Al(CH₃)₃, freezes at c. 0° and boils at 140°.

Aluminium ethyl, Al(C₂H₅)₃, boils at 194°.

Aluminium propyl boils at 248° to 252°. Aluminium isobutyl and aluminium isoamyl are also known.

At temperatures only slightly higher than their boiling-points, aluminium methyl and aluminium ethyl consist almost exclusively of double molecules Al₂(CH₃)₆ and Al₂(C₂H₅)₆. The vapour densities diminish rapidly with rise of temperature, but it is not possible to state definitely to what extent this diminution is to be attributed to the dissociation Al₂(Alk.)₆ ⇔ 2Al(Alk.)₃, since it appears probable that decomposition also commences. In ethylene dibromide solution, aluminium ethyl has a molecular weight in harmony with the double formula.