Spin Quantum Number M
Most recent answer: 03/17/2016
Q:
What is the spin quantum number for the last electron in Potassium (The 4S^1). How can we know whether it is +1/2 or -1/2.
- Parth Patel (age 18)
Etobicoke, Ontario, Canada
- Parth Patel (age 18)
Etobicoke, Ontario, Canada
A:
The simple answer is that the ground state is degenerate, so there is no definite m value. Measurement will be equally likely to find +1/2 or -1/2.
If you put the atom in a magnetic field, thereby breaking the degeneracy, the ground state's spin will tend to align with the magnetic field.
If we consider the spin of the nucleus there could be a preference for the 4S electron to align with it. But that is a very weak effect, part of the "hyperfine structure."
Richard
(published on 03/17/2016)