Question

A cations is smaller than Anion... Explain......

Answer 1

Hey !

Solution:

Cations are positively charged ions which are formed by attaining the nearest noble gas configuration. For example : Na⁺ ions have only 10 electrons while Na element has 11 electrons. Na⁻ will have 12 electrons as it's valency is 1. But anions are not possible for for metals, but Na⁻ is just taken for consideration.

So according to electronic configuration,

Na⁺ = 10 Electrons

=> Electron Configuration = 2,8 which have only 2 shells.

Na⁻ = 12 electrons

=> Electron Configuration = 2, 8, 2 electrons which have 3 shells.

So since there is an extra shell in the anion, the anion has a greater size. And since the cation has only 2 shells, the size of the cation is smaller than anion.

Hope it helped !