Question

Which of the following statements do not form a part of Bohr's model of hydrogen atom?

• A. Energy of the electrons in the orbits are quantised
• B. The electron in the orbit nearest the nucleus has the lowest energy
• C. Electrons revolve in different orbits around the nucleus
• D. The position and velocity of electrons in the orbit cannot be determined simultaneously

Answer 1

The Correct Option is D

To determine which statement does not form a part of Bohr's model of the hydrogen atom, let's evaluate each option based on the established principles of Bohr's atomic model.

1. Energy of the electrons in the orbits are quantised: Bohr's model posits that electrons revolve around the nucleus in fixed orbits and each orbit corresponds to a specific energy level. Thus, the energy of electrons is quantised, meaning that electrons can only occupy certain energy levels and not between them. This statement is a fundamental part of Bohr's model.
2. The electron in the orbit nearest the nucleus has the lowest energy: According to Bohr's model, the energy levels are negatively quantised. The closer the electron is to the nucleus (or lower the orbit), the lower its energy. This statement aligns perfectly with Bohr's model.
3. Electrons revolve in different orbits around the nucleus: Bohr's model specifically describes electrons moving in different circular orbits or energy levels around the nucleus without radiating energy. This statement is an essential part of Bohr's atomic theory.
4. The position and velocity of electrons in the orbit cannot be determined simultaneously: This statement is a reflection of the Heisenberg Uncertainty Principle, not Bohr's model. The Uncertainty Principle states that it is impossible to measure both the position and momentum (or velocity) of a particle simultaneously with absolute precision. This quantum mechanical concept was introduced after Bohr's model as a limitation of the classical view depicted by Bohr. Therefore, it does not form a part of Bohr's model.

Conclusion: The statement "The position and velocity of electrons in the orbit cannot be determined simultaneously" is not part of Bohr's model of the hydrogen atom, as it pertains to the Heisenberg Uncertainty Principle introduced in quantum mechanics.