46) (a) n = 2, l = 1, ml = 1
This is a permissible set of quantum numbers because n = 2, and l = 1 represents a 2p sublevel which is valid for an excited hydrogen atom. A 2p sublevel has 3 orbitals, -1, 0, +1.
(b) n = 1, l = 0, ml = -1
This is not a permissible set because l = 0 represents an s sublevel for which ml must equal 0.
(c) n = 4, l = 2, ml = -2
This is a permissible set because n = 4 and l = 2 represents an electron in the 4d sublevel and ml = -2 is a valid orbital in the d sublevel.
(d) n = 3, l = 3, ml = 0
This is not a permissible set because when n = 3, you can only have 3 sublevels s, p , and d. An f sublevel is not valid.