Isoelectronic species have same no. of electrons. Below are the isoelectronic species with their respective no. of electrons:
K+18Cl−18Ca2+18Sc3+18
All of the above elements have the electronic configuration of argon.
Which one of the following sets of ions represents a collection of isoelectronic species?
(Given : Atomic Number :F:9,Cl:17,Na=11
Mg=12,Al=13,K=19,Ca=20,Sc=21)
Held on 1 Feb 2023 · Verified 6 Jul 2026.
(Li+,Na+,Mg2+,Ca2+
(Ba2+,Sr2+,K+,Ca2+
(N3−,O2−,F−,S2−
(K+,Cl−,Ca2+,Sc3+
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