Exams › JEE Main › Chemistry
Which one of the following sets of ions represents a collection of isoelectronic species?
- N³−, O²−, F−, S²−
- Li⁺, Na⁺, Mg²+, Ca²+
- K⁺, Cl^−, Ca²+, Sc³+
- Ba²+, Sr²+, K⁺, Ca²+
Correct answer: K⁺, Cl^−, Ca²+, Sc³+
Solution
The ions K⁺, Cl^−, Ca²+, and Sc³+ all have the same number of electrons, specifically 18, making them isoelectronic. This means they share the same electron configuration, which is a key characteristic of isoelectronic species.
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