Question

Which of the following has the largest atomic size ?

• A. $Al$
• B. $A{l}^{2+}$
• C. $A{l}^{3+}$
• D. $A{l}^{+}$

Answer 1

The correct option is A $Al$

A cation will always be smaller than its neutral atom. This is because, cations are formed with the loss of electrons. Hence there are a lesser number of electrons and hence greater effective nuclear attraction as a result of which the ionic radius decreases. In the above case, $Al$ is the largest in size.