## Quantum Numbers

Shannon Asay 1C
Posts: 102
Joined: Fri Aug 09, 2019 12:16 am

### Quantum Numbers

What are the differences between the angular momentum quantum number and the magnetic quantum number and how do you calculate them?

Chem_Mod
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Joined: Thu Aug 04, 2011 1:53 pm
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### Re: Quantum Numbers

The angular momentum number denotes the subshell (e.g. s, p, d) the electron is in while the magnetic quantum number denotes the number of orbitals you can have for that specific subshell. The possible values you can have for the angular momentum quantum number are 0, 1, ... n-1 with n being the principal quantum number. The possible values you can have for the magnetic quantum number are -l...0...l, with l being the specific angular momentum number that you are looking at.

John Arambulo 1I
Posts: 58
Joined: Sat Jul 20, 2019 12:15 am

### Re: Quantum Numbers

In addition to what Chem_Mod said about angular momentum quantum number and magnetic quantum number, the angular momentum quantum number describes the 'shape' of the orbital while the magnetic quantum number describes the orientation in space of the different orbitals of a subshell.

chari_maya 3B
Posts: 108
Joined: Sat Sep 07, 2019 12:18 am

### Re: Quantum Numbers

why are higher orbitals (g-,h- etc) not used by chemists in practice?

Aman Sankineni 2L
Posts: 103
Joined: Fri Aug 30, 2019 12:17 am

### Re: Quantum Numbers

I believe they are used in more complicated experiments and more detailed chemistry, but in terms of this class, we probably won't be going over them since those elements don't come up.

005384106
Posts: 101
Joined: Sat Aug 24, 2019 12:16 am

### Re: Quantum Numbers

How does an atoms energy level relate to n and l?

005384106
Posts: 101
Joined: Sat Aug 24, 2019 12:16 am

### Re: Quantum Numbers

Does l represent energy level?

005384106
Posts: 101
Joined: Sat Aug 24, 2019 12:16 am

### Re: Quantum Numbers

Can I clarify why the n is always less that 1 of l.

Ashley R 1A
Posts: 41
Joined: Sat Aug 24, 2019 12:16 am

### Re: Quantum Numbers

for the principal quantum number n, keep in mind that all energies are measured as negative because it's relative to the energy of the free electron. When you start at n=1, this is the first energy level so it will be the lowest and most negative energy level, and as you increase n, energy will subsequently increase. Since n goes backwards, then the highest energy level will be n=0, which is when the electron escapes the nucleus.

Ashley R 1A
Posts: 41
Joined: Sat Aug 24, 2019 12:16 am

### Re: Quantum Numbers

Regarding your second question reply, l represents the shape inside an energy level, and it represents the orbital angular momentum quantum number. To my understanding, within a hydrogen atom, all the orbitals in a shell will have the same energy despite what shape it has, but this isn't true for atoms with more than one electron.