Question

Which shows the atoms in order of decreasing atomic radii? A) F, Cl, Br B.) Cl, F, O C) S, Cl, F D) N, C, B

Answer 1

Answer:C) S, Cl, F shows the decreasing order of atomic radii across a period and down a group

Explanation:

The Trend of  atomic radius in a period occurs like this :

decreases from left to right as you go across a period. This is because of the shrinking of the nucleus  as electrons are being added to the same orbital or shell conferring on the nucleus a positive charge as  protons are also  being  added to the nucleus causing an attraction of the positively charged nucleus to electrons.

Increase down the group-This is because of the increasing energy levels caused by an increase in the number of shell causing a gap between outermost shell and the nucleus.

--Therefore  On the same group, as you move across the period 3, Sulphur has a larger atomic radius than chlorine  and on group 17  chlorine has a larger atomic radius than Fluorine.