Question

The principal quantum number describes ____

(a) energy and size of the orbit

(b) the shape of the orbital

(c) spatial orientation of the orbital

(d) the spin of the electron

I got this question in an interview.

Asked question is from Quantum Mechanical Model of Atom topic in section Structure of Atom of Chemistry – Class 11

Answer 1

Right answer is (a) energy and size of the orbit

To elaborate: Among the four quantum numbers, the principal quantum number describes the size and energy of the orbit. It is represented by the symbol “n”. For shells, K, L, M, N and O, n is given by 1, 2, 3, 4 and 5.