What is the oxidation number of the metal in #GaCl_2#?
Net Oxidation State of a molecule should be zero.
In Chloride Ion Form, Cl has a charge of -1.
So Oxidation State of Chloride is -1.
Let The Oxidation State of Gallium be x.
Hence explained the answer.
This is clearly
Oxidation state/number is the charge left on the central atom, when all the other bound atoms are removed, with the charge devolving to the most electronegative atom........
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