Question

The chemical reactivity of the elements of group 1 increases downwards while that of the elements of group 17 decrease downwards . Explain by giving reasons

Answer 1

Answer :-

Group 1 :- Because of addition of one extra shell.

Group 2 :- Because of the Increasement of charge they are attracted towards nucleus and get collapsed.

Reason :-

Case :1-

In case of group 1 elements the atomic radius increases because of increase of an extra shell which increases the distance between the nucleus to outermost shell of an atom.

Case : 2-

In case of electronegative elements or halogens group 17 the atomic radius decreases because the number of protons increases but the shell number is same and thus the nucleus attract the outermost shell and it get collapsed towards nucleus and thus decrease between nucleus and outermost shell decrease.