Target Exam

CUET

Subject

Physics

Chapter

Atoms

Question:

Consider two different hydrogen atoms. The electron in each atom is in first excited state. According to Bohr's model, electrons will have:

Options:

different energies but the same orbital angular momentum

same energies and the same orbital angular momentum

same energies but different orbital angular momentum

different energies and no orbital angular momentum

Correct Answer:

same energies and the same orbital angular momentum

Explanation:

The correct answer is Option (2) → same energies and the same orbital angular momentum

According to Bohr's model of hydrogen atom -

(A) Energy of the electron in the first excited state (n = 2) depends upon only on the Quantum number n, and since both the the hydrogen atom have electron in the same excited state (n = 2), the energy of the electrons will be same.

(B) The orbital angular momentum of an electron -

$L=nh$

for $n=2$, the orbital angular momentum for both atoms will be, as $L=2h$.