Hello there,
<span>Al has an oxidation number of 3 and Cl has 1. So, the most likely formula unit of the compound is AlCl3.
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Glad to help.
~hottwizzlers
The only following substance that is not fluid is air
Chemical formulas for ionic compounds are written in lowest common multiples of the charges of each ion. This is true unlike covalent compounds where the transformation to lowest common multiple is not applicable such that this reflects to the naming of covalent compounds using prefixes mono-, di-, tri-, tetra-, etc. Answer is a.