Question

The atomic radii of first group elements are given below:
Group-I element Atomic radii(pm)






Na 86
K 231
Rb 244
Cs 282 State the reason behind the observed trend in the above elements. ​

Answer 1

Answer:

As u go down in a group, the atomic radii increase

Explanation:

As u movedown a group, the size of atom increases bcoz one shell is added to each element as u move down...so distance btw nucleus and outermost shell increases, and hence atomic radius also increases

Answer 2

This shows that the atomic size or radii is going on increasing when we move from top to bottom in group.

Explanation:

Atomic radii

It is the distance between the center of nucleus to the outermost shell of an atom.

     Now as we move from top to bottom , the number of shells increase and hence the distance between the nucleus and outermost shell also increase.

This causes increase in atomic radii.