It fails for multi-electron atoms, cannot explain fine structure or the Zeeman effect, and violates the uncertainty principle.
Practise Atomic Structure & Periodicity All Atomic Structure & Periodicity topics
The Bohr model works well only for one-electron species, because it cannot handle the electron-electron repulsions in multi-electron atoms. It fails to predict the relative intensities of spectral lines and does not account for fine structure in full detail. It cannot fully explain the Zeeman effect, and it does not reproduce the spectra of most atoms. Conceptually it conflicts with the Heisenberg uncertainty principle, since it assigns electrons exact circular orbits with definite radii and momenta. The model was replaced by the wave mechanics of Schrodinger and others.
Key ideas: It fails for atoms with more than one electron, cannot explain fine splitting of lines, intensity of lines, Zeeman and Stark effects, and chemical bonding. It violates the uncertainty principle by specifying radius and momentum, and predicts a ground state with angular momentum h / 2 pi, whereas the true 1s state has zero.
Common mistakes and connections: Students believe it was simply wrong; it correctly predicted hydrogen energies, which the quantum treatment reproduces. Another error is thinking electrons move in orbits in modern chemistry; they occupy orbitals described by probability. These limitations led to de Broglie, Heisenberg and Schrodinger.
Bohr's model is exact for hydrogen but gives 54.4 eV for helium if electron repulsion is ignored, versus the true 24.6 eV. The interactive lesson shows this as a live animation or chart.
The model predicts the wrong spectrum for helium, which has two electrons, because it cannot treat their mutual repulsion.
It fails for multi-electron atoms, cannot explain fine structure or the Zeeman effect, and violates the uncertainty principle.
Limitations of Bohr Model is a intermediate topic in Atomic Structure & Periodicity. It builds on the vocabulary of beginner topics in this area.
Study these earlier topics in Atomic Structure & Periodicity first: Rydberg Equation, Bohr Model, Bohr Energy Levels.
The next topics in Atomic Structure & Periodicity are de Broglie Hypothesis and Heisenberg Uncertainty Principle.
Yes. The interactive lesson includes a self-check question on Limitations of Bohr Model, and the Atomic Structure & Periodicity quiz draws on every topic in this area.
Limitations of Bohr Model is topic 47 of 115 in Atomic Structure & Periodicity.