Exaplain each qauantum number and describe the electronic configuration of element

Identify the sets of quantum numbers that describe all the electrons in a neutral beryllium atom, Be. Each set is ordered (n,l,ml,ms)

I'm not sure how to find even one set......Please Help!

The principle quantum number (n) tells the energy level an electron is in. Has values 1, 2, 3, 4 ...  depending on the energy level the electron is located in.

The secondary quantum number (l) tells the subshell (or shape of the orbital and electron is in. Has values from 0 to n-1.  0 = s subshell, 1= p subshell, 2= d subshell, etc

The third quantum number (ml) indicates the particular orbital an electron is in.  Has values of -l to +l.  For instance if l=1 (p subshell), ml has three possible values -1, 0, and +1 corresponding to the three orbitals that make up a p subshell.

The 4th quantum number (ms)indicates the spin of the electron.  Has values of +1/2 and -1/2 indicating the two types of spin an electron can have.

A Be atom has 4 electrons:

There quantum numbers would be:

1st electron in 1s orbital with positive spin:  1, 0, 0, +1/2
2nd electron in 1s orbital with negative spin: 1, 0, 0, -1/2
3rd electron in 2s orbital with positive spin:  2, 0, 0, +1/2
4th electron in 2s orbital with negative spin: 2, 0, 0, -1/2

Great thanks! At first I didn't understand why the long hand 1s, 1s, 2s, 2s. But, I think its because of how many electrons in the element, right?

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