JEE Main 2024 · ChemistryNumerical answerNumerical valueEasyCalculation

JEE Main 30 January 2024, Shift 2, Chemistry Q81

Question 81 of 90 in this shift, Chemistry question 21 of 30, Section B.

Number of spectral lines obtained in

\mathrm{He^+}

spectra, when an electron makes transition from fifth excited state to first excited state will be

Official answer

NTA final key.

Chapter: Structure of Atom
Topic: Bohr's Atomic Theory
Idea tested: Number of Spectral Lines in Transitions

Same topic in other shifts

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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 42 of the 174 JEE Main shifts held from 2017 to 2026.