## Textbook 1D.13

Melody Haratian 1B
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Joined: Wed Sep 30, 2020 9:48 pm
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### Textbook 1D.13

Hi everyone!
I need a bit of help on 1D.13 part (a) and part (b). The problem states “(a) How many values of the quantum number l are possible when n=7? (b) How many values of ml are allowed for an electron in a 6d-subshell?”. Does anyone know how to get started on this problem, or any strategies on how to solve it?
Thank you

Ethan Laureano 3H
Posts: 62
Joined: Wed Sep 30, 2020 9:58 pm

### Re: Textbook 1D.13

For part a, l starts at 0 and can only go up to n-1. So this means a max of l=6. The values will be l= 0,1,2,3,4,5,6 (7 values). As for ml, it is the values of -l to l. In this case, the l value for d is 2. So the ml will be -2,-1,0,1,2. This corresponds with the 5 orbitals in the d subshell.

Rich Luong 1D
Posts: 60
Joined: Wed Sep 30, 2020 9:49 pm

### Re: Textbook 1D.13

So for part A, you're able to get 7 numbers of l because l = n-1. So to list it out, your values of l when n= 7 would be 0, 1, 2, 3, 4, 5, and 6. For part B, the ml values will depend on the l value. So since the electron is in a d subshell, the greatest value of l would be 2. Given 2, your ml values will vary from -l all the way to l, listing out -2, -1, 0, 1, and 2. So in total, that is 5 values of ml. I hope this helps!

Sofia Lucido 3L
Posts: 74
Joined: Wed Sep 30, 2020 9:51 pm

### Re: Textbook 1D.13

Hi,

For this question you can use the guidelines for the values of l and ml when you know n and l, respectively:

l can equal 0 all the way up to n-1. So if n=7 then l can equal 0 all the way up to 7-1 which is 6 (so l can equal 0, 1, 2, 3, 4, 5, 6)

ml can equal -l all the way up to l. So for part b) a 6d subshell tells us that n=6 and the d tells us that l=2 because l=2 corresponds to the d subshell. Because l=2, ml can equal -2 all the way up to 2 (so -2, -1, 0, 1, 2)