Orbital with different magnetic quantum numbers are degenerate (same energy) in the absence of magnetic and electric fields. Sum of the Principal and Azimuthal quantum number (n + l) determine the energy of the orbitals.
Higher the (n + l) value of the orbital, larger the energy of the orbital. If the orbitals have same (n + l) value, then orbital with higher ‘n’ value, has the higher energy.
