Question

How and why does the atomic size vary as you go:

(i) from left to right along a period?

(ii) down a group?

PLS ANSWER FAST!!!

Answer 1

1.On moving across a period the atomic size of an element decrease because of increase in nuclear charge...

2.on moving down a group the atomic size of an atom increases because of increase in number of shells......

Answer 2

As you move from left to right the atomic size decrease because of more protons pulling the electrons inward and as you move down the periodic table the size increases due to the fact that the number of shells increases resulting in the size becoming large.
Hope Im right. Didnt do this for a long time. Im not guarantee if it is correct.