Which of the following are isoelectronic species?

Which of the following are isoelectronic species?
  1. $\mathrm{O}^{2-}, \mathrm{F}, \mathrm{Na}^{+}, \mathrm{Mg}^{+}$
  2. $\mathrm{O}, \mathrm{F}^{-}, \mathrm{Na}, \mathrm{Mg}$
  3. $\mathrm{O}^{2-}, \mathrm{F}^{-}, \mathrm{Na}^{+}, \mathrm{Mg}^{2+}$
  4. $\mathrm{O}^{2-}, \mathrm{Cl}^{-}, \mathrm{Na}, \mathrm{Mg}^{2+}$

Solution

$\mathrm{O}^{2-}, \mathrm{F}^{-}, \mathrm{Na}^{+}$and $\mathrm{Mg}^{2+}$ are isoelectronic species. They contain 10 electrons each.

Asked in: AP EAMCET 2020 (22 Sep Shift 2)

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