Which of the four quantum number (n, l, `m_(l), m_(s)`) determine (a) the energy of an electron in a hydrogen atom and in a many electron atom (b) the size of an orbital (c) the shape of an orbital (d) the orientation of an orbital in space ?

Explanation

(a) Energy of electron in hydrogen atom is determined by n and in a many electron atom by n and l
(b) Size of the orbital is determined by n
(c) Shape of the orbital is determined by l
(d) Orientation of the orbital is determined by `m_(l)`