Question

what is variable valency in chemistry

Answer 1

 In transition elements, an atom loses electrons from the shell next to the valence shell (penultimate shell). In such a situation the element exhibits more than one valency (variable valency). For example: Iron has 2 electrons in its valence shell. On donating these electrons, its valency is 2+.

Answer 2

ʜᴏʟᴀ ᴍᴀᴛᴇ !

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⭐ᴀɴsᴡᴇʀ⭐

Certain elements combine with other atoms, donating, accepting or sharing electrons in different proportions depending on the nature of the reaction. For example, iron combines with oxygen to form ferrous oxide as well as ferric oxide. This is termed variable valency.