Write down the limitations of Bohr's model.

(N/A) $(i)$ It fails to account for the finer details (doublet,that is two closely spaced lines) of the hydrogen atom spectrum observed by using sophisticated spectroscopic techniques.
This model is also unable to explain the spectrum of atoms other than hydrogen (e.g.,helium atom or ion which have more than one electron).
- Zeeman effect: Bohr's theory was unable to explain the $H$ spectrum in the presence of a magnetic field.
- Stark effect: Bohr's theory was unable to explain the $H$ spectrum in the presence of an electric field.
- Bohr's theory was unable to explain the splitting of spectral lines.
$(ii)$ It could not explain the ability of atoms to form molecules by chemical bonds.