Question

why first members of each group of representative elements shows anomalous behaviour illustrate with two examples​

Answer 1

Answer:

First member of each group of representative elements (i.e, s- and p-block elements) shows anomalous behaviour due to i) small size, ii) high ionisation enthalpy, iii) high electonegartivity and (iv) absence of d-orbitals e.g. in s-block elements, lithium shows anomalous behaviour from rest of the alkali metals.

Explanation: