Question

O^2-, F^–, Na^+ and Mg^2+ are called as __________

(a) Isoelectronic species

(b) Isoneutral species

(c) Isotopes

(d) Isobars

The question was asked in an international level competition.

My question is from Periodic Trends in Properties of Elements topic in portion Classification of Elements and Periodicity in Properties of Chemistry – Class 11

Answer 1

Correct option is (a) Isoelectronic species

The best explanation: O^2-, F^–, Na^+ and Mg^2+ are known as isoelectronic species as they all have the same no. of electrons(10). Isotopes contain the same no. of protons but a different number of neutrons. Isobars have the same mass number but a different atomic number.