Spin Magnetic Quantum Number

Moderators: Chem_Mod, Chem_Admin

KMcFarland_2L
Posts: 90
Joined: Wed Sep 30, 2020 9:52 pm

Spin Magnetic Quantum Number

Postby KMcFarland_2L » Fri Oct 23, 2020 3:46 pm

The spin magnetic quantum number can either be +1/2 or -1/2 based on if the electron is spun up or down, but how do you determine which direction it is spun?

Brianne Conway 1D
Posts: 91
Joined: Wed Sep 30, 2020 9:36 pm

Re: Spin Magnetic Quantum Number

Postby Brianne Conway 1D » Fri Oct 23, 2020 3:48 pm

I don't think we need to know how to actually determine it; I'm pretty sure that has to do with Schrodinger's equation. We just need to know which number signifies which spin.

Margia Adriano 2A
Posts: 84
Joined: Wed Sep 30, 2020 10:00 pm

Re: Spin Magnetic Quantum Number

Postby Margia Adriano 2A » Fri Oct 23, 2020 4:26 pm

Hi! I don't think it is too important or necessary for us to know whether an electron is spin up or down, just that you know the ms=+1/2 is spin up and ms=-1/2 is spin down and that a filled orbital cannot have two of the same. Hope this helps!

Katie Phan 1K
Posts: 93
Joined: Wed Sep 30, 2020 9:55 pm

Re: Spin Magnetic Quantum Number

Postby Katie Phan 1K » Fri Oct 23, 2020 4:48 pm

Yes, I don't think you need to know how to determine it, just need to know the quantum numbers.

Linette Choi 3L
Posts: 88
Joined: Wed Sep 30, 2020 9:51 pm

Re: Spin Magnetic Quantum Number

Postby Linette Choi 3L » Sun Oct 25, 2020 11:43 pm

I also don't believe you need to know how to calculate it. However, you can determine the spin by the number of electrons in the atom. For instance, using Hund's rule, for an element like Carbon which is 1s2 2s2 2p2, the two S orbitals are filled with arrows, however with the remainder of the arrows, only two of the P orbital are filled with positive arrows. This would indicate that there is a positive +1/2 spin in the P orbital.

Ex: ↑ ↓ ↑ ↓ ↑ ↑
1s2 2s2 2p2

Samudrala_Vaishnavi 3A
Posts: 93
Joined: Wed Sep 30, 2020 9:34 pm

Re: Spin Magnetic Quantum Number

Postby Samudrala_Vaishnavi 3A » Mon Oct 26, 2020 8:47 am

For the spin magnetic quantum number, the +1/2 indicates up and the -1/2 indicates down. We were never taught how to actually calculate the spin, but there is some conceptual knowledge about how it was discovered in the first place which could guide your understanding. The Stern and Gerlach experiment that we learned about tells us why there are only two different spin numbers and how this correlates to unpaired electrons. Just some things to note, remember that if you are doing an electron configuration that you note the electrons per orbital as spin up first and then spin down for the s orbital and for the p, d, and f orbitals use spin up to fill all the orbitals and THEN spin down to pair them once you have filled all the orbitals of the subshell.

Nicoli Peiris 1B
Posts: 100
Joined: Wed Sep 30, 2020 10:02 pm

Re: Spin Magnetic Quantum Number

Postby Nicoli Peiris 1B » Mon Oct 26, 2020 1:20 pm

I don’t think we have to know that. Just know +1/2 spin up and -1/2 is spin down!


Return to “Quantum Numbers and The H-Atom”

Who is online

Users browsing this forum: No registered users and 2 guests