Question

Which of the following is biggest in size?

• A. $Ca$
• B. $C{a}^{+}$
• C. $C{a}^{2+}$
• D. $C{a}^{-}$
• E. $C{a}^{2-}$

Answer 1

The correct option is E $C{a}^{2-}$

Since anions are larger than the corresponding neutral atom formed by the addition of the electrons, adding electrons increases the number of electron-electron repulsion interactions that take place. Cations are smaller than the corresponding neutral atoms formed by the loss of electrons, since the valence electrons, which are furthest away from the nucleus are lost.So greater the anionic charge larger is the size of anion.So $Ca$ atom with $-2$ charge is largest in size.