Which of the following isoelectronic species has the largest size?

Question

Which of the following isoelectronic species has the largest size? (A)  Na+ (B) O2- (C) N3- (D) F-

Tardigrade Admin · Accepted Answer

All the ions are isoelectronic but they have different size due ot different values of Z. In Na +, O 2-, N 3-, F -, number of electrons are 10 but, r propto (1/Z). Thus greater the value of (e/Z) greater the size of iso-electronic species. Hence N 3- is largest in size.

Q. Which of the following isoelectronic species has the largest size?

$N a^{+}$

$O^{2 -}$

$N^{3 -}$

$F^{-}$

Q. Which of the following isoelectronic species has the largest size?

Na+

O2−

N3−

F−

All the ions are isoelectronic but they have different size due ot different values of Z. In Na+,O2−,N3−,F−, number of electrons are 10 but, r∝Z1​. Thus greater the value of Ze​ greater the size of iso-electronic species. Hence N3− is largest in size.

$N a^{+}$

$O^{2 -}$

$N^{3 -}$

$F^{-}$