Spin Magnetic Quantum #

[Ella Bogomilsky 2B]

Why is the spin magnetic quantum number 1/2? Does it represent the speed or direction of the electron’s spin?

[Lindsay Beckwith 2B]

The spin magnetic quantum number indicates both magnitude and direction. This number can only be +1/2 or -1/2 because each orbital can only hold two electrons (so each one accounts for either +1/2 or -1/2). Each electron in the orbital spins in opposite ways, either in the positive or negative direction.

[Alex Yeghikian 1C]

I think there is a complicated quantum mechanics reason for the number being 1/2. It has something to do with the electron as a particle, and matches the mathematical models, so it is the accepted number.

[Sonia Virk 2A]

the 1/2 represents the spin of the electrons and is also either +1/2 for spin up or -1/2 for spin down. The upward spin is the first half of electrons and those upward spin electrons are paired with downward spin electrons after the first electron is filled for each place (Hund's rule).