aluminum trichloride

chemical compound

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June 18, 2026

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Aluminum trichloride (AlCl₃) is a compound of aluminum, a lightweight, silvery-white metal that is the most abundant metallic element in Earth's crust. Aluminum trichloride is a Lewis acid and is commonly used as a catalyst in organic chemistry, particularly in Friedel-Crafts reactions. It is also used in the cosmetic industry as a deodorant.12

In its solid form, aluminum trichloride has an ionic lattice structure that conducts electricity. However, upon melting, it transitions to a covalent state, forming dimeric molecules with the formula Al₂Cl₆. This transition highlights the delicate energy balance between ionic and covalent bonding in aluminum compounds.3

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boron group element
Trihalides
The electrical conductivity of solid aluminum trichloride (formula AlCl₃), in which each aluminum ion has three positive charges, increases rapidly as the temperature is elevated toward the melting point, at which the conductivity suddenly falls to zero. This phenomenon occurs because the aluminum and chloride ions form an ionic lattice…
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The electrical conductivity of solid aluminum trichloride (formula AlCl₃), in which each aluminum ion has three positive charges, increases rapidly as the temperature is elevated toward the melting point, at which the conductivity suddenly falls to zero. This phenomenon occurs because the aluminum and chloride ions form an ionic lattice…
Read More