00:02
To answer this question we need to know the values of the four quantum numbers.
00:09
In other words what they can be and what those mean.
00:12
So first of all our principal quantum number n that describes the energy level.
00:20
And it is an integer that must be positive.
00:27
So we know that the energy level closest to the nucleus is given the value n equals 1.
00:33
And then the increase in value as you move away from the nucleus.
00:36
All right next we want to talk about the angular momentum quantum number l which describes the subshell.
00:48
L can have a value that is an integer and let's just say from rather than between.
01:03
So an integer from 0 to n minus 1.
01:09
Therefore if n were 3 for example l could be 0, 1 or 2 because 3 minus 1 gives us 2.
01:20
Furthermore actually i want to go on with that when l equals 0 that describes an s orbital.
01:30
When l equals 1 that describes a p.
01:33
When l equals 2 that describes a d orbital.
01:37
And when l equals 3 that would be an f orbital.
01:41
All right next we have m sub l that's the magnetic quantum number.
01:47
And it also must be an integer from negative l to positive l.
01:56
If l were 2 for example then m sub l would have to be negative 2, negative 1, 0, 1 or 2.
02:06
Finally m sub s the spin quantum number can only have one of two possible values.
02:11
Either positive one half or negative one half...