Question

Na+ is isoelectronic with (a) Mg2+ (b) O2- (c) Cl- (d) O​

Answer 1

Answer:

(a) and (b)

Explanation:

Isoelectronic species are elements having equal number of electrons

Answer 2

Na⁺ is isoelectronic with Mg²⁺ and O²⁻.

• Two atoms or ions are said to be isoelectronic if the number of electrons in their shells is equal in number.
• Na has a total of 11 electrons. Na⁺ has one electron lesser than Na. So, it has 10 electrons.
• Mg has a total of 12 electrons. Mg²⁺ has two electrons lesser than Mg. So, it has 10 electrons.
• O has a total of 8 electrons. O²⁻ has two electrons more than O. So, it has 10 electrons.
• Cl has a total of 17 electrons. Cl⁻ has one electron more than Cl. So, it has 18 electrons.
• Hence, Mg²⁺ and O²⁻ are isoelectronic with Na⁺.