Problem 32

Given information

 Few isoelectronic species are given. Those are :.

These must be arranged   according to the increasing atomic radius.

Step-by-step explanation

Isoelectronic species are those species having equal number of electrons.

atomic radius is the measure of size of an element.

 has atomic number   thus on adding two more electron it has   electron

 has atomic number     thus on removing electron it has  electron

 has atomic number    thus on removing one  electron it has  electron

 has atomic number    thus on adding one more electron it has  electron

For isoelectronic species those having less number of proton has more radius. Thus those species with lowest atomic number will have more radius 

Order of atomic radius will be <<<.