'''Principle quantum number''' - corresponds to the main [[electron shell]] in which the electron resides. Can have the value n=1, 2, 3 up to 7 corresponding to shells with increasing amounts of energy | '''Principle quantum number''' - corresponds to the main [[electron shell]] in which the electron resides. Can have the value n=1, 2, 3 up to 7 corresponding to shells with increasing amounts of energy |