Question

why some elements show variable valency​

Answer 1

Because of the diffrent electronic confirguation .

An atom of element can some times lose more electrons than are present in its valence shell, lose from the penultimate shell and hence exhibit more than 1 or variable valency

Answer 2

Some elements show variable valency because of the different electronic configurations. An atom of an element can sometimes lose more electrons than are present in its valence shell i.e. loss from the penultimate shell and hence exhibit more than 1 or variable valency

Explanation:

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