Polarization

Bohr’s model of the atom was a significant advancement in understanding atomic structure. However, it had limitations. Let’s examine the given statements:

Step 1: Analyze each statement.
(A) It fails to account for the finer details of the hydrogen atom spectrum.
This is correct. Bohr's model cannot explain the fine structure or hyperfine splitting in the hydrogen spectrum. These fine details were later explained by the quantum mechanical model of the atom. (B) Unable to explain the splitting of spectral lines in the presence of magnetic field.
This is also correct. Bohr's model cannot explain the Zeeman effect, which is the splitting of spectral lines in the presence of a magnetic field. This phenomenon requires quantum mechanics for a proper explanation. (C) The angular momentum of electron is quantised.
This statement is correct. One of the key features of Bohr’s model is that the angular momentum of an electron is quantised. Bohr proposed that the angular momentum of electrons in certain orbits is restricted to discrete values.

Step 2: Identify the incorrect statement.
(D) The ability of atoms to form molecule by chemical bonds.
This statement is incorrect in the context of Bohr’s model. Bohr's model does not address the ability of atoms to form molecules or the nature of chemical bonding. This concept is better explained by quantum mechanics and the molecular orbital theory. (E) Unable to explain the splitting of spectral lines in the presence of magnetic field.
This is a repeat of statement (B), and it is correct. Bohr’s model does not explain the splitting of spectral lines in the presence of a magnetic field (the Zeeman effect).

Final Answer: (D) The ability of atoms to form molecule by chemical bonds.