Question

Find the correct set with iso electronic species?

• A. $N ^{3-}, F ^{-}, O _{2}, Ca ^{2+}$
• B. $Ca ^{2+}, Cl ^{-}, Al ^{3+}, O _{2}^{-}$
• C. $N ^{3-}, Mg ^{2+}, F ^{-}, O ^{2-}$
• D. $Mg ^{2+}, O _{2}{ }^{-} Cl ^{-}, N _{3}^{-}$

Answer 1

Answer: (C)

Iso-electronic species Atoms, molecules and ions that have the same electronic configuration are said to be iso-electronic. So, Number of electrons
(a)

$N^{3-}$	$=10$
$F^{-}$	$=10$
$O_{2}$	$=16$
$Ca ^{2+}$	$=10$

Number of electrons
(b)

$Ca^{2+}$	$=10$
$Cl^{-}$	$=18$
$Al^{3+}$	$=10$
$ O_2^-$	$=17$

Number of electrons
(C)

$N^{3-}$	$=10$
$Mg^{2+}$	$=10$
$F^-$	$=10$
$O^{2+}$	$=17$

Number of electrons
(d)

$Mg^{2+}$	$=10$
$O^{-}_2$	$=17$
$Cl^{-}$	$=10$
$N_3^-$	$=22$