## Determining Quantum Numbers

IsabelMurillo3K
Posts: 60
Joined: Wed Sep 30, 2020 9:51 pm

### Determining Quantum Numbers

On Sapling, there are a couple questions regarding determining the number of electrons an atom could hold. For example, one question gives us the conditions of when n=7, l=1, and m=-1. I was wondering how I would go figuring out this problem? Thanks in advance!

Astha Patel 2J
Posts: 66
Joined: Wed Sep 30, 2020 10:03 pm
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### Re: Determining Quantum Numbers

So the first three quantum numbers specify an orbital. Each orbital can hold a maximum of 2 electrons. So the first three quantum numbers can specify at most 2 electrons. Once the fourth quantum number is given, then the four numbers specify a single electron.
Hope this helps :)

Kelly Tran 1J
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Joined: Wed Sep 30, 2020 9:50 pm
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### Re: Determining Quantum Numbers

I agree with Astha! The first 3 quantum numbers (n, l, and ml) can be the same for 2 electrons.

Eva Becker
Posts: 54
Joined: Wed Sep 30, 2020 9:40 pm

### Re: Determining Quantum Numbers

n refers to the total number of orbitals (i think).

for the s subshell: l=0
p subshell: l=1
d: l=2

ml is the negative value of l to the positive value (i.e. if l=2, ml=-2, -1, 0, 1, 2)

Ellison Gonzales 1H
Posts: 64
Joined: Wed Sep 30, 2020 10:00 pm

### Re: Determining Quantum Numbers

I know how to get the answer of ml from l, but what does ml stand for conceptually? I believe in the lecture he said that ml is the allowed values, but I don’t completely understand what that means. Thank you

Manseej Khatri 2B
Posts: 55
Joined: Wed Sep 30, 2020 9:42 pm

### Re: Determining Quantum Numbers

Hi. The ml quantum number is the orientation of the orbital. For example in the 2p subshell, you can have the individual orbitals oriented 2px, 2py, 2pz. With l being angular momentum, ml essentially is the orientation of the angular momentum.