## n and l numbers

Brendan Duong 1I
Posts: 69
Joined: Wed Sep 30, 2020 10:07 pm

### n and l numbers

So my understanding is (and correct me if I'm wrong) n is the number/coefficient in front of the orbital. So n for 7s^2 is 7. My main point of confusion is for the l number. I've written down from lecture that l is equal to 0,1, up to n-1. But Ive also seen others just say that l is just 0 for s orbital, 1 for p, 2 for d, and 3 for f. So which of the two is it? What is n and l for 7p^5?

Akash J 1J
Posts: 73
Joined: Wed Sep 30, 2020 9:58 pm
Been upvoted: 1 time

### Re: n and l numbers

For 7p5, n = 7, l = 1.

You are right, for the angular momentum number (l), l=0 indicates the s subshell, l=1 indicates the p subshell, etc. However if you look at n = 1 (the first period with H and He), p can only equal 0, showing that you can only have the s subshell when n=1.
When n = 2, you can have l = 0, 1 indicating that the s and p subshells are possible. The trend continues until the f subshell (l=3) because after f, we don't currently have subshells to be characterized by l=4, 5, 6...

MinjooPark_3I
Posts: 79
Joined: Wed Sep 30, 2020 9:33 pm

### Re: n and l numbers

Hii. So l represents the shape of an orbital or specific subshell. l=0 is s, l=1 is p, l=2 is d, and l=3 is f.

Sonel Raj 3I
Posts: 67
Joined: Wed Sep 30, 2020 9:48 pm

### Re: n and l numbers

The thing that has helped me most when learning about orbitals is looking at their positions in the periodic table. N corresponds to the period number, and if we were, for example, to only look at n=1, we would see that there are only two elements, and therefore only one possible subshell. For n=2, there is the s-subshell and the p-subshell only. If you can understand how the quantum numbers fit into the periodic table (there should be more resources online!) it can help you understand conceptually. :)

Shruti Kulkarni 2I
Posts: 72
Joined: Thu Oct 08, 2020 12:16 am

### Re: n and l numbers

Hi! Generically, the corresponding orbitals do follow the pattern l = 0 is s, l = 1 is p, l = 2 is d, and l = 3 is f. So, for the 7p^5 example you mentioned, it would have quantum numbers of n = 7 and l = 1, as you are in the p-orbital.

Joey_Okumura_1E
Posts: 82
Joined: Wed Sep 30, 2020 9:58 pm

### Re: n and l numbers

n represents the shell. l represents the subshell. ml represents the orbital. Therefore, for 7p5, n=7; l=1 indicates it is a p orbital; and ml would indicate if it was a px orbital, py orbital, etc.