MCQ
The simple Bohr modle is not applicable to He$^4$ atom because:
  • A
    He$^4$ is an inert gas.
  • B
    Electrons are not subject to central forces.
  • C
    He$^4$  has one more electron.
  • B and C both

Answer

Correct option: D.
B and C both
Solution:
Bohr model applies only to a Hydrogen-like atom (or atom having one electron). 2He$^4$ atom has two electrons. Also, these electrons are not subject to central forces.

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