JEE Main 2023 — s Block Elements Question with Solution
JEE Main 2023 (24 Jan Shift 2)
Question
The number of s-electrons present in an ion with protons in its unipositive state is
Choose an option
Show full solutionCorrect option: D
Correct answer
D
Step-by-step explanation
The atom with 55 protons is caesium(Cs). The electronic configuration of Cs is .
The mono positive ion means one electron is removed from outermost orbital. Hence, the sum of electrons in orbitals are.
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This is a previous-year question from JEE Main 2023, covering the s Block Elements chapter of Chemistry. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.