## 2.29

Rucha Kulkarni 2A
Posts: 43
Joined: Fri Sep 29, 2017 7:05 am

### 2.29

Is there a specific method to solving this question?
How many electrons can have the following quantum numbers in an atom: (a) n =2, l = 1; (b) n =4, l = 2,
ml = -2; (c) n = 2; (d) n = 3, l = 2, ml = -1?

Jonathan Tangonan 1E
Posts: 50
Joined: Sat Jul 22, 2017 3:01 am

### Re: 2.29

A)
When you're are given the n and l to find the total number of possible electrons you determine the possible ml values and and multiply the number of possible ml values by 2. ml is l, l-1,...-l.

n=2; l=1 so the subshell is p.
This means that ml can be -1,0,1 and 2 electrons can fill each of those orbitals resulting in 6 possible electrons.

B) When given n, l, and ml that means you are given one specific orbital within a certain subshell. So within that specific orbital there can be 2 electrons.
n=4; l=2; ml=-2
So there are 2 possible electrons.

C) When you are only given n, you have to determine the possible l and ml values to figure out the total number of possible electrons. When you figure out the total number of possible ml values, you multiply the possible ml values by 2.

n=2
l= 0;1 which means there is a 2s subshell and 2p subshell
ml= for 2s it's 0 and for 2p it can be -1,0,1
so in total there are 4 different ml values; 4x2=8 possible electrons.

Gurvardaan Bal1L
Posts: 54
Joined: Fri Sep 29, 2017 7:04 am
Been upvoted: 2 times

### Re: 2.29

Jonathan Tangonan wrote:A)
When you're are given the n and l to find the total number of possible electrons you determine the possible ml values and and multiply the number of possible ml values by 2. ml is l, l-1,...-l.

n=2; l=1 so the subshell is p.
This means that ml can be -1,0,1 and 2 electrons can fill each of those orbitals resulting in 6 possible electrons.

B) When given n, l, and ml that means you are given one specific orbital within a certain subshell. So within that specific orbital there can be 2 electrons.
n=4; l=2; ml=-2
So there are 2 possible electrons.

C) When you are only given n, you have to determine the possible l and ml values to figure out the total number of possible electrons. When you figure out the total number of possible ml values, you multiply the possible ml values by 2.

n=2
l= 0;1 which means there is a 2s subshell and 2p subshell
ml= for 2s it's 0 and for 2p it can be -1,0,1
so in total there are 4 different ml values; 4x2=8 possible electrons.

Just wanted to expand on this and also add an explanation for part D

Since n=3, l=2, and ml= 1(that means within the third principal quantum level, in the d subshell's 4th orbital) there are two electrons that can possibly be there.