Question

17. The correct arrangement of the following elements in order of

Answer 1

Answer:

Got your back

Explanation:

If the ions derived from different atoms are isoelectronic species, then they all have same number of electrons in their electronic shells and will have got same electronic configuration but their nuclear charge will differ because of their difference in number of protons in the nucleus. With increase in number of protons in the nucleus the electrons are more attracted towards nucleus thereby causing the decrease in ionic radius. On this principle our problem will be solved

The given ions are

7N-3

→no. of proton

=7

and

no of electron

=10

8O-2

→

no. of proton

=8

and

no of electron

=10

9F-→

no. of proton=9

and no of electron=10

11Na→

no. of proton=11

and no of electron=10

12 Mg-3→

no. of proton=12 and

no of electron=10

Hence the increasing order of ionic radius is

12Mg-3<11Na+<9F-<8O-2<7N-3

To rmember ->For isoelectronic species lower the nuclear charge higher the radius