Question

Be²⁺ is isoelectronic with which of the following ions?
[2014]
(a) H⁺ (b) Li⁺
(c) Na⁺ (d) Mg²⁺

Answer 1

Answer:

Explanation:

Li+ and Be+ ions have same number of electrons, so they are isoelectronic.

Answer 2

Isoelectronic species with Be²⁺ in given options are - (b) Li⁺

Isoelectronic species are the ones containing same number of electrons. Beryllium has four electrons. In its ionic form, it will have total two electrons.

Lithium has three electrons. In its ionic form, it will contain two electrons. Hence, the two ions mentioned are isoelectronic in nature.

Sodium has eleven electrons, and in ionic form it contains ten electrons. Magnesium has twelve electrons, and in ionic form it contains ten electrons.