00:02
Hi there.
00:03
We have two questions here pertaining to quantum numbers.
00:07
So i want to briefly talk about the quantum numbers.
00:11
The first quantum number n, that is the principal quantum number.
00:18
And that tells you the energy level.
00:21
Or in other words, distance from the nucleus.
00:31
It can be an integer or a whole number with one being the lowest and then on up from that.
00:39
With the higher the number, the further you get from the nucleus.
00:45
Okay, the next quantum number is the angular momentum quantum number, and this describes the shape of the orbital.
00:57
It, too, is a whole number, or an integer, and it ranges from zero to n -minus -1, and it describes the shape of the orbital as followed.
01:11
When l equals zero, we have an s -orbital.
01:16
When l equals 1, it's a p, when l equals 2, it's a d, and when l equals 3, it's an f orbital.
01:27
Next we have the magnetic quantum number, m sub l, and that tells you the orientation of the orbital in space.
01:39
It is an integer that ranges from negative l to positive l.
01:45
So whatever l is, m sub l ranges from negative l to positive l.
01:50
And then the fourth quantum number is the spin quantum number.
01:54
It is m sub s, and it can only be one of two possible values, either positive one -half or negative one -half.
02:05
And if you have two electrons occupying the same orbital, one of them will be positive one -half spin, and the other will be negative one -half.
02:14
So the first three quantum numbers describe the orbital, while the last quantum number, describes the electron.
02:32
Okay, so this should be enough information to look at our questions here.
02:38
Let's see if i can keep as much of this in view as possible.
02:46
It's not cooperating.
02:51
All right, well, we'll go with what we can see here.
02:54
So in our first one, we have n equals four.
02:58
So that means the fourth energy level.
03:01
L equals three.
03:02
Let's think about what that means.
03:03
That means an f orbital, an m subel, equals two.
03:10
Well, that just means one of the f orbitals.
03:13
So we know we're in the fourth energy level, and it is an f orbital.
03:21
We know that there are seven f orbitals.
03:30
At any energy level that has f orbitals, there are seven of those f orbitals of equal energy.
03:45
Therefore, the correct answer here, it cannot be the first one because this is not in the third energy level.
03:52
It's in the fourth.
03:54
And it's not a p orbital.
03:55
It's an f orbital...