(2) Ca2+=20−2=18e− Ar=18e−K+=19−1=18e−Cl−=17+1=18e− So, Ca2+,Ar,K+and Cl−are isoelectronic species.
Which one of the following represents all isoelectronic species?
Held on 30 Apr 2023 · Verified 9 Jul 2026.
Na+,Mg2+,O−,F−
Ca2+,Ar,K+,Cl−
Na+,Cl−,O−,NO+
N2O,N2O4,NO+,NO
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