Question

Assertion (A) : In a group electronegativity decreases on moving down the group. Reason (R) : This is due to the effect of decreased atomic radius.

Answer 1

Answer:

In the same period, electrons are filled in same shell.

So, they are not able to screne each other. Thus the nuclear charge as well as effective nuclear charge increases. Thus the radius decreases.

In the group, however new shells are added and thus the radius increases.

Thus the assertion and Reason are true and reason explains the assertion