Question

In a group I of the periodic table, three elements $X,Y,andZ$ have ionic radii 1.33 $A^0$ , 0.95 $A^0$, and 0.60 $A^0$ respectively. Giving a reason, arrange them in the order of increasing atomic numbers in the group.

Answer 1

The ionic radii of the elements are given $X=1.33A^0,Y=0.95A^0,andZ=0.60A^0$

• As the ionic radius increases, the atomic size increases. The number of electrons also increases, and thus, the atomic number increases.

Therefore, the increasing order of atomic
numbers of the elements is $Z<Y<X$..