## n,l,ml,and ms

ariaterango_1A
Posts: 57
Joined: Wed Sep 18, 2019 12:15 am

### n,l,ml,and ms

Hi! I was wondering what the conceptual differences are between n,l,ml,and ms. Which is considered the orbital, the shell, or the subshell? Thank you!

Reina Robles 2B
Posts: 71
Joined: Fri Aug 09, 2019 12:16 am

### Re: n,l,ml,and ms

n is the shell, l is the subshell, ml is the orbital, and ms is the electron's spin. I hope this helps!

Sion Hwang 4D
Posts: 51
Joined: Wed Sep 18, 2019 12:21 am

### Re: n,l,ml,and ms

These variables are all quantum numbers of atoms, describing where you might be able to find electrons in an atom.

n is the principle quantum number, which describes the energy and size of the atom, or how many shells the atom has. In other words, it tells of how distant electrons are from the nucleus. The number n is however many shells the atom has (or the period number). In a ground state electron configuration, it is the highest shell the electron can be at. So if you took calcium, for instance, the configuration is [Ar]4s2. Hence, n=4, since the 4th shell is the outermost shell of calcium.

l is the angular momentum quantum number. It describes the shape of the atom. l is all the numbers from 0 to n-1. For instance, if you had an atom with n=4, then l would be 0, 1, 2, and 3.
Each l value corresponds to a subshell (s, p, d, f, g, h, so on). The l value also states how many angular nodes the atom can have, therefore determining shape.
Again, an atom with n=4 would have l values 0, 1, 2, and 3, or -s, -p, -d, -f subshells. There would also be 4 angular nodes.

ml is the magnetic quantum number, which determines the orbitals of a subshell. ml is all numbers from -l to +l. Thus, if n=3, l would equal 0, 1, and 2, and ml would be -2, -1, 0, 1, and 2. To exemplify, a p subshell (l=1) can have ml values of -1, 0, or 1. These values correspond to the px, py, and pxy orbitals (and again, remember that each orbital can only fill 2 electrons).

ms is the spin magnetic quantum number, which determines whether an electron is spinning up or down. It can either have a +1/2 value (which is spinning up) or a -1/2 value (spinning down). The spin number determines whether an unparalleled electron can create a magnetic field.