In the Bohr model of the atom, do electrons exist in fixed orbits where they cannot move from one level to another?
Yes to a certain degree
The electrons do exist in fixed orbits BUT when the electrons are excited, they will move up an energy level. Once the energy used to excite the electron is released, the electron moves downwards back to its initial energy level.
Also, the Bohr model cannot be accepted as the correct model because of the following:
- doesn't explain why electrons occupy discrete energy levels
- it uses the assumption that electrons behave like simple classical particles but do not radiate energy as they move ie when they move, it doesn't lose energy and spiral into the nucleus
There are other theories such as the Heisenberg uncertainty principle and the probability principle