Question

Which of the following is not isoelectronic series?

• A.
• B.
• C.
• D.

Answer 1

The correct option is D

$N^{-3}\to 7+3=10e^{-}=S^{2-}\to 16+2=18e^{-};C{l}^{-}=17+1=18e^{-}$

They are not a set of isoelectronic species as they have a different number of electrons.