Question:
Consider the isoelectronic species, Na+, Mg2+, F–and O2–. The correct order of increasing length of their radii is _________.
(i) F– < O2- < Mg2+ < Na+
(ii) Mg2+ < Na+< F–< O2-
(iii) O2-< F– < Na+< Mg2+
(iv) O2- < F– < Mg2+ < Na+
Solution:
Option (ii) Mg2+ < Na+< F–< O2- is the answer.