Explain why cation is smaller and anion is larger in radii than their parent atoms.

Explanation

`rarr` Cation means a positively charged species which is formed by an atom (or) element when an electron is lost.
`M rarr M^(+) + e^(Θ)`
`rarr` Catuib has high effective nuclear charge and decrease in size observed. Hence cation has smaller radii.
`rarr` Anion means a negatively charged species which is formed by an atom (or) element when an electron is gained.
`M + e^(-) rarr M^(Θ)`
`rarr` Anion has very low effective nuclear charge and increase in size observed. Hence anion has larger radii.