Question

how does the atomic radius of the elements change on going(1) from left to right in a period .(2) down a group,in the modern periodic table ? given readon in supportof your answer.

Answer 1

(1) the atomic radius decreases so we go from left to right. This is because of the adding in the nuclear charge of the elements’ atoms by 1 unit as we go from one element to the next.This increased nuclear charge tends to pull the electrons on the outer shells inwards, thereby reducing the atomic radius
(2)as we go down a group, the atomic radii of the elements increase. Even though there is an addition in the nuclear charge(as we saw in (1)),the size still increases as there are new shells being added as we go down

Hope it helps ya

Answer 2

i ). The atomic radius of an element INCREASES on moving from Left to Right in a Period..

Reason>> It is because the distance between the electrons and the nucleus decreases with the decrease in atomic size so their tendency to gain electrons increases as the forces of attraction between them make it difficult to lose electrons..( non metals)..



ii ). The atomic radius of an element INCREASES down a Group on moving from top to bottom..


Reason>> It is because the distance between the electrons and the nucleus INCREASES with the Increase in atomic size so their tendency to lose electrons Increases as the forces of attraction between them decreases which makes it convenient to lose electrons..




Hope it helps;)