Bohr’s Atomic Theory

Bohr's atomic model

1. The electrons revolve around the nucleus in paths called orbits, each having a certain energy level.
2. Electrons do not emit energy when revolving in a stationary state.
3. Electrons emit or absorb energy when they shift from one energy level to another.
4. The angular momentum of an electron is an integral multiple of $h/2\pi$, where $n = 1, 2, 3, \ldots$

Shortcoming of Bohr's atomic model

• Electrons are not restricted to a single plane Bohr's model suggested that electrons move in circular orbits within one plane, but later studies showed that electrons occupy three-dimensional regions around the nucleus.
• It could not explain spectra of multi-electron atoms Bohr's theory successfully described the hydrogen atom, but it failed to explain the complex spectral lines of atoms with more than one electron.
• It did not address chemical bonding The model ignored how electrons participate in forming chemical bonds, which is essential for understanding molecular structure and reactions.
• It contradicted Heisenberg's Uncertainty Principle Bohr assumed electrons had definite paths and positions, but Heisenberg showed that it is impossible to know both the exact position and velocity of an electron at the same time.