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					Quantum Numbers
   Ryan Morrison & Ally Gray
                                          What are Quantum Numbers?
•    Specify the properties of an atomic orbital.

•    An orbital is where an atom keeps its electrons.




                                                     orbitals


     Each element on the periodic table has a different set of Quantum Numbers, like their own address.
     The primary rule of quantum numbers is that no two elements can have the same set of numbers,
     this principle is also known as the Pauli Exclusion Principle.

For example:         Nitrogen                                            Oxygen

                 n=2 l=1 m=1 s=+½                                n=2 l=1 m=(-1) s=(- ½)

These two elements may have a very similar address but it is not the same.
                                n
n represents the number of the orbital.
 •Whatever row the
 element is in, is
 the number you 
 place for ‘n’.
•This number tells us
the energy level and
shell that the electron
is found in.

 The higher a value for n,
 means a higher amount       •The principal quantum number (n)
 of energy and the further   cannot be zero. The allowed values of
 away it is from the         n are therefore 1, 2, 3, 4, and so on.
 nucleus.
                                                l
     l represents the subshell
There are 4 different sub shells, they are 0, 1, 2 or 3 & are all represented by letters.
    s is the purple (considered as 0)
    p is the green (considered as 1)
    d is the yellow (considered as 2)
    f is the blue   (considered as 3)
This quantum number characterizes the
electrons angular momentum and
determines the shape of the orbit.

Its possible values for an electron depend
on the value of that electron's principal
                                              If n = 1, the only   If n = 2, the only
quantum numbers, ranging from 0 to n-1.
Because of these different possibilities,     possible value for   possible values for
shells (other than the first shell) include   quantum number l     quantum number l
subshells. These are designated as            is 0 (s).            are 0 & 1 (s & p)
s(where l=0), p (where l=1), d (where l=2),
and f (where l=3)                                       If n = 3+, the possible values
                                                        for quantum number l are
                                                        0,1,2,3, (s,p,d,f)
                                               m
      m represents magnetism.
      The m orbital corresponds with the l orbital (subshells). If the subshell was d, it would
      be equal to saying that m is: -2 ≤ m ≤ 2 or if the shell was p it would be -1 < m > 1. The
      value of m indicates the orientation of the electron's orbit within the subshell.

 m can range from 0 to a positive or negative number depending on the subshell.
   For each column periodic table, the
   magnetism that would be your number
   for m is constant . If you find that your
   number is bigger than 3 or smaller than
   -3, you are incorrect because L only
   ranges from -3<m<-3.


Example: if l = 2 then your m values will be:
-2, -1, 0, 1, 2,  repeated twice to fill the column.
                                            s
    s represents spin.
•   Moves in a circular/spherical shape

•   Contains either a positive or
    negative charge.

•   A positive spin means the electrons
    spin clockwise. (+½)

•   A negative spin means the electron
    spins counter-clockwise. (- ½)

•   The first half of each orbital is + ½
    and the other half is – ½ .
           Examples.
n=4
l=2
m = -2
s = +1/2
n=3

l=1


m=0

s = +1/2
n=4         m=0
      l=0         s = +1/2

				
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posted:9/13/2012
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