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Karnataka Board PUCPUC Science 2nd PUC Class 12

The simple Bohr model cannot be directly applied to calculate the energy levels of an atom with many electrons. This is because ______.

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Question

The simple Bohr model cannot be directly applied to calculate the energy levels of an atom with many electrons. This is because ______.

Options

  • of the electrons not being subject to a central force.

  • of the electrons colliding with each other.

  • of screening effects.

  • the force between the nucleus and an electron will no longer be given by Coulomb’s law.

MCQ
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Solution

The simple Bohr model cannot be directly applied to calculate the energy levels of an atom with many electrons. This is because of the electrons not being subject to a central force.

Explanation:

The simple Bohr model cannot be directly applied to calculate the energy levels of an atom with many electrons because when we derive the formula for radius/energy levels etc, we make the assumption that centripetal force is provided only by the electrostatic force of attraction by the nucleus. Hence, this will only work for single electron atoms. In multi-electron atoms, there will also be repulsion due to other electrons. The simple Bohr model cannot be directly applied to calculate the energy levels of an atom with many electrons.

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Chapter 12: Atoms - Exercises [Page 76]

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NCERT Exemplar Physics Exemplar [English] Class 12
Chapter 12 Atoms
Exercises | Q 12.03 | Page 76

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