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Chemistry · Structure of Atom

JEE Main 2026 — 22 January, Morning Shift — Question 52

The energy required by electrons, present in the first Bohr orbit of hydrogen atom to be excited to second Bohr orbit is ____\_\_\_\_ Jmol−1\mathrm{J} \mathrm{mol}^{-1}.

(Given : RH=2.18×10−11\mathrm{R}_{\mathrm{H}}=2.18 \times 10^{-11} ergs)

  1. Option A:

    1.635×10−181.635 \times 10^{-18}

  2. Option B:

    9.835×1059.835 \times 10^{5}

    Correct
  3. Option C:

    9.835×10129.835 \times 10^{12}

  4. Option D:

    1.635×10−111.635 \times 10^{-11}

Answer: B

Step-by-step solution

Energy level, En=−RHn2E_n = -\frac{R_H}{n^2}

On converting, we have

= 2.18 \times 10^{-18} \text{ J}$$ Energy absorbed, $\Delta E = R_H\left(1 - \frac{1}{4}\right) = \frac{3}{4}R_H$ $= 1.635 \times 10^{-18} \text{ J (per\; atom)}$ Per mole, $\Delta E = 1.635 \times 10^{-18} \times 6.02 \times 10^{23}$ $= 9.835 \times 10^5 \text{ J mol}^{-1}$ Hence, the correct option is B.

Answer key and solution verified before publishing.

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Exam
JEE Main 2026
Paper
22 January, Morning Shift
Subject
Chemistry
Chapter
Structure of Atom
Topic
Bohr's Model of Atom
The energy required by electrons, present in the first Bohr orbit of… | JEE Main 2026 PYQ with Solution · DhiX AI