identify the element from the following four quantum numbers:?

Question

1.) n=2
2.) l=1
3.)ml=-1
4.)ms= -1/2

how do u get these? please show work

Answer 1

This is boron:

n=2 the second valence shell has an electron

l=1 the s orbital (l=0) is filled and there are electrons in the p orbital

ml = -1 the px orbital is occupied, but not the py (ml=0) or pz (ml=1).

ms= -1/2 There is only one electron in the px orbital, or ms would equal +1/2.

Answer 2

STEP1
n=2 the element can only be in the second row of periodic table
so you can only chose the elements between Li and Neon

STEP 2

l=1 you can exclude Li and Be since there have only l=0

STEP 3

The element must have odd number of electrons on its outer subshell. This can be due to one electron on this shell
so eelement should be B