Which orbital is being occupied
^^^^ WRONG
UPDATE 1/12/16: APEX ANSWER IS The energy level of the electron.
The energy level of the electron
N = 2
n=3
This is the principal quantum number, n.
n=2
n = 3
n is the first quantum number. It is the principle quantum number. It refers to what energy level it is and will be one greater than the number of nodes in the orbital. l is the second quantum number. It is the angular momentum quantum number and refers to the shape of the orbital. ml is the third quantum number. It is the magnetic quantum number and it refers to the orientation of the orbital. ms is the fourth quantum number. It is the spin quantum number and refers to the magnetic character of the orbital.
N = 2
n=3
This is the principal quantum number, n.
n=2
The first quantum number (n) represents the energy level (shell), so for a 1s2 electron, it would have a value of 1.
There are several different quantum numbers for a given atom (principle quantum number, the angular quantum number, the magnetic quantum number, the spin quantum number, etc) .I assume you are looking for the Principle Quantum number, n, which is equal to the row (period) in the period table in which the element is situated.For helium, the principle quantum number is 1.i.e. n = 1As another example; the principle quantum number for potassium (K), n = 4.
n = 3
n=1
n = 2
3s has a principle quantum number of n=3 5s has a principle quantum number of n=5
the inner energy level of an atom has a maximum # of