Question

In the Bohr model of hydrogen atom, the angular momentum of the electron is:

• A. Quantized as multiples of \( h \)
• B. Continuous
• C. Quantized as multiples of \( \frac{h}{2\pi} \)
• D. Equal to zero

Hint:

In Bohr's model, angular momentum is quantized:
\[ L = n \cdot \frac{h}{2\pi} = n\hbar \] This was key in explaining the discrete energy levels in atoms.

Answer 1

The Correct Option is C

According to Bohr's quantization rule, the angular momentum of an electron in a hydrogen atom is quantized. This means the electron can only occupy certain allowed energy levels.
Bohr's postulate:
\[ L = n \cdot \frac{h}{2\pi} \quad \text{where } n = 1, 2, 3, \dots \] So, the angular momentum is not just any value — it is a whole number multiple of \( \frac{h}{2\pi} \), not of \( h \).
Why not the other options?
- (A) Quantized as multiples of \( h \): incorrect — should be \( \frac{h}{2\pi} \).
- (B) Continuous: Bohr’s theory explicitly proposed quantization.
- (D) Equal to zero: This is not true; lowest level still has non-zero angular momentum.