3.2 Quantum Numbers Flashcards
What is the Principal Quantam Number, n? Describe its characteristics.
a positive whole number that indicates the energy level and relative size of an atomic orbital
~ aka “shell”
n can have values from 1 to infinity, however 1 to 7 practically
~ as n values increase, so does size and energy level
What is the Orbital Shape Quantam number, l? Describe its characteristics.
an integer that describes the shape of atomic orbitals within each principal energy level
~ aka “sublevel” or “subshell”
l can have values from 0 to n-1
(ex. if n=3, l = 0 or 1 or 2)
each value of l can be identified by a letter
~ l = 0 (s)
~ l = 1 (p)
~ l = 2 (d)
~ l = 3 (f)
What is the Magnetic Quantam Number, ml? Describe its characteristics.
an integer that indicates the orientation of an orbital in the space around a nucleus
~ can have values from -l to +l
(ex. if l = 2 then ml = -2, -1, 0, 1, or 2 )
- an atomic orbital can contain a max of 2 electrons
- # of orbitals at an energy level n is n^2
- max # of electrons at an energy level n is 2n^2
What is the Spin Quantam Number, ms? Describe its characteristics.
The quantam number that specifies the orientation of the axis on which the electron is spinning
~ ms can have values of +1/2 (spin up) or -1/2 (spin down)
What is the pauli exclusion principle
- a max number of 2 electrons can occupy an orbital
- electrons in an orbital must have OPPOSITE spins
- each electron in an atom has a unique set of 4 quantam numbers
What is the exception for Cr?
[Ar] 4s1 3d5
What is the exception for Mo?
[Kr] 5s1 4d5
What is the exception for Cu?
[Ar] 4s1 3d10
What is the exception for Ag?
[Kr] 5s1 4d10
What is the exception for Au?
[Xe] 6s1 4f14 5d10
What did Heisenberg propose?
an uncertainty principle that says that it is not possible to exactly define both the position and momentum (speed); the more you define one value, the less you know about the other
