An electron in a hydrogen atom has orbital quantum number l = 4. How many possible values of the magnetic quantum number ml could it have?
A) 4
B) 10
C) 5
D) 9
E) 3

Question

Quizplus · Accepted Answer

The magnetic quantum number $ m_l $ can take values from $-l$ to $+l$, including zero. For $ l = 4 $, $ m_l $ can be $-4, -3, -2, -1, 0, 1, 2, 3, 4$, which gives 9 possible values.

An Electron in a Hydrogen Atom Has Orbital Quantum Number