Question

i) Define atomic size. How does it very in a period & a group.​

Answer 1

Answer:

In general, the atomic radius decreases as we move from left to right in a period with an increase in nuclear charge of the element. The atomic radius increases when we go down a group because of the addition of extra shell.

Answer 2

Answer:

atomic size decreases from moving left to right

that is while moving from left to right the elements reduces it's tendency to lose electrons since the atoms are pulled towards nucleus .

On moving across a period atomic size decreases because of the electron increases by 1

in groups, the atomic size increases down the group as the differentiating electron enters into the new quantum shell.