What is the correct order of atomic/ionic size ?

Options

A. `Cu^(+) lt Cu lt Zn^(2+) lt Ag`
B. `Zn^(2+) lt Cu^(+) lt Cu lt Ag`
C. `Ag lt Cu lt Cu^(+) lt Zn^(2+)`
D. `Cu^(+) lt Zn^(2+) lt Cu lt Ag`

Answer

B

Explanation

Neutral atom tend to increases size down the group and across a period due to electromagnetic interaction between electrons in an atom modify the `Z_("eff")`.
`Z_("eff") = Z-S`= sheilding effect
As an additional electrons occupies the electrons in outer shell and protons in the nucleus. So, the `Z_("eff")` increases.
As an neutral atoms that have lost an `e^(-)` exhibit a positive charge and are called cations and therefore `Z_("eff")` increases.
So, the order of ionic radii is `Zn^(2+) lt Cu^(+) lt CU lt Ag`.