Q3 / 160 · TS EAMCET 2020 (11 Sep Shift 1) · Chemistry

Find the correct set with isoelectronic species?

  • A
    $\mathrm{N}^{3-}, \mathrm{F}^{-}, \mathrm{O}_2, \mathrm{Ca}^{2+}$
  • B
    $\mathrm{Ca}^{2+}, \mathrm{Cl}^{-}, \mathrm{Al}^{3+}, \mathrm{O}_2^{-}$
  • Correct answer
    C
    $\mathrm{N}^{3-}, \mathrm{Mg}^{2+}, \mathrm{F}^{-}, \mathrm{O}^{2-}$
  • D
    $\mathrm{Mg}^{2+}, \mathrm{O}_2^{-}, \mathrm{Cl}^{-}, \mathrm{N}_3^{-}$

Solution

Iso-electronic species Atoms, molecules and ions that have the same electronic configuration are said to be iso-electronic. So, Number of electrons (a)$\begin{array}{ll}\mathrm{N}^{3-} & =10 \\\mathrm{~F}^{-} & =10 \\\mathrm{O}_2 & =16 \\\mathrm{Ca}^{2+} & =10\end{array}$ Number of electrons (b)$\begin{array}{ll}\mathrm{Ca}^{2+} & =10 \\\mathrm{Cl}^{-} & =18 \\\mathrm{Al}^{3+} & =10 \\\mathrm{O}_2^{-} & =17\end{array}$ Number of electrons (c)$\begin{array}{ll}\mathrm{N}^{3-} & =10 \\\mathrm{Mg}^{2+} & =10 \\\mathrm{~F}^{-} & =10 \\\mathrm{O}^{2-} & =10\end{array}$ Number of electrons (d)$\begin{array}{ll}\mathrm{Mg}^{2+} & =10 \\\mathrm{O}_2^{-} & =17 \\\mathrm{Cl}^{-} & =18 \\\mathrm{~N}_3^{-} & =22\end{array}$ Hence, correct option is (c).

Hence, the correct answer is option: 'C'.

Relevant Questions