Question

Which of the following set of quantum numbers is not valid?

(a) n = 5, l = 2, m = 0, s = 1/2

(b) n = 1, l = 2, m = 0, s = 1/2

(c) n = 5, l = 3, m = 2, s = 1/2

(d) n = 5, l = 2, m = 0, s = -1/2

I have been asked this question in an internship interview.

My question is taken from Quantum Mechanical Model of Atom topic in division Structure of Atom of Chemistry – Class 11

Answer 1

Right option is (b) n = 1, l = 2, m = 0, s = 1/2

To explain: The set of quantum number n = 1, l = 2, m = 0, s = 1/2, is not valid because the value of azimuthal quantum number should lie only in between 0 and n-1, where n is principal quantum number. So the above set of quantum numbers is not valid.