Question

How do the valency and the atomic size of the elements vary while going from left to right along in the modern period table ​

Answer 1

hyy mate ✌️

On moving from left to right in the periodic table, valency increases up to 4 and then decreases. ... On moving across a period atomic size decreases because of the electron increases by 1 whereas, the number of valence shell remains the same. Therefore as a result of an increase in nuclear charge, atomic radius decreases.

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Answer 2

Answer:

$<font color ="red">$ Atomic size decreases on going along a period from left to right because the electron enters into the same shell, therefore, attraction between nucleus and outermost electron increases and thus atomic size decreases. Valency first increases from 1 to 4 and then decreases from 4 to 0 along a period from left to right.