Well, your collection of quantum numbers is not "allowed" because that a particular electron since of the worth you have for #"l"#, the angular momentum quantum number.

The values the angular momentum quantum number is permitted to take go from zero come #"n-1"#, #"n"# gift the principal quantum number.

You are watching: How many different values of l are possible for an electron with principal quantum number n = 2?

So, in her case, if #"n"# is same to 3, the worths #"l"# have to take room 0, 1, and also 2. Because #"l"# is noted as having the value 3, this puts it external the allowed range.

The worth for #m_l# deserve to exist, due to the fact that #m_l#, the **magnetic quantum number, arrays from #-"l"#, to #"+l"#.

Likewise, #m_s#, the spin quantum number, has an agree value, due to the fact that it can only be #-"1/2"# or #+"1/2"#.

Therefore, the only value in your set that is not permitted for a quantum number is #"l"=3#.


Answer connect
*

Michael
january 18, 2015

There room 4 quantum number which explain an electron in one atom.These are:

#n# the major quantum number. This speak you which energy level the electron is in. #n# have the right to take integral values 1, 2, 3, 4, etc

#l# the angular momentum quantum number. This tells you the form of sub - covering or orbit the electron is in. That takes integral values varying from 0, 1, 2, approximately #(n-1)#.

If #l# = 0 you have actually an s orbital.#l=1# offers the p orbitals#l=2# gives the d orbitals

#m# is the magnetic quantum number. For directional orbitals such together p and also d it tells you exactly how they room arranged in space. #m# can take integral values of #-l ............. 0.............+l#.

#s# is the spin quantum number. Put simply the electron have the right to be considered to it is in spinning top top its axis. Because that clockwise turn #s#= +1/2. Because that anticlockwise #s# = -1/2. This is often shown as #uarr# and also #darr#.

In your concern #n=3#. Let"s usage those rules to view what worths the other quantum numbers deserve to take:

#l=0, 1 and 2#, yet not 3.This offers us s, p and also d orbitals.

If #l# = 0 #m# = 0. This is one s orbitalIf #l# = 1, #m# = -1, 0, +1. This offers the three p orbitals. Therefore #m# = 0 is ok.If #l# = 2 #m# = -2, -1, 0, 1, 2. This provides the five d orbitals.

#s# deserve to be +1/2 or -1/2.

See more: What Does Off The Chain Mean ? Off The Chain

These are all the allowed values because that # n=3#

Note that in one atom, no electron have the right to have every 4 quantum number the same. This is just how atoms are accumulated and is known as The Pauli exemption Principle.