Question

Which of the following sets does not represent isoelectronic species?

• A. $Ne,F^{-},O^{2-}$
• B. $C{l}^{-},Ar,K^{+}$
• C. $S^{2-},B{r}^{-},Kr$
• D. $M{g}^{2+},N{a}^{+},Ne$

Answer 1

Answer: (C)

$Ne\Rightarrow 10F\Rightarrow 9+1=10O^{2-}\Rightarrow 8+2=10$

$C{l}^{-}\Rightarrow 17+1=18Ar\Rightarrow 18K^{+}\Rightarrow 19-1=18$

$S^{2-}\Rightarrow 16+2=18B{r}^{-}\Rightarrow 35+1=36Kr=36$

$M{g}^{2+}\Rightarrow 12-2=10N{a}^{+}\Rightarrow 11-1=10Ne=10$