MCQ
The pair, in which ions are isoelectronic with $Al ^{3+}$ is ..... .
  • A
    $Br ^{-}$and $Be ^{2+}$
  • B
    $Cl ^{-}$and $Li ^{+}$
  • C
    $S ^{2-}$ and $K ^{+}$
  • $O ^{2-}$ and $Mg ^{2+}$

Answer

Correct option: D.
$O ^{2-}$ and $Mg ^{2+}$
d
Isoelectronic species have same no. of electrons $Al ^{+3}, O ^{2-}, Mg ^{+2}$ all have $10$ electrons.

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