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Chemistry · Structure of Atom

JEE Main 2025 — 22 January, Morning Shift — Question 34

Radius of the first excited state of helium ion is ______\_\_\_\_\_\_.

(Given: a0a_0 = radius of first stationary state of hydrogen atom)

  1. Option A:

    r=a02r=\frac{a_{0}}{2}

  2. Option B:

    r=a04r=\frac{a_{0}}{4}

  3. Option C:

    r=4a0r=4 a_{0}

  4. Option D:

    r=2a0r=2 a_{0}

    Correct

Answer: D

Step-by-step solution

Bohr radius relation, rn=a0n2Zr_n = a_0 \frac{n^2}{Z}

For He+\mathrm{He^+}, we have

Z=2, n=2Z=2,\ n=2

= 2a_0$$

Answer key and solution verified before publishing.

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Exam
JEE Main 2025
Paper
22 January, Morning Shift
Subject
Chemistry
Chapter
Structure of Atom
Topic
Bohr's Model of Atom
Radius of the first excited state of helium ion is \ \ \ \ \ \ .… | JEE Main 2025 PYQ with Solution · DhiX AI