Transcript Electron Configuration Notes

Electron Energy Level Notes
Purpose of Lesson
• learn the structure of
atomic orbitals because
they are basic to chemical
bonding.
Starting Question
• Make a Venn diagram
comparing the Rutherford
model of the atom with
the Bohr Model and the
quantum orbital model.
Starting Question
•How is preparing for
a quiz similar to
preparing for an
athletic competition?
Electron Energy Level Notes
• Electrons do not travel around the nucleus
of an atom in orbits
• They are found in energy levels at different
distances away from the nucleus. (kind of like
shells or layers--see picture on p. 87).
• They cannot exist between energy levels
(just like the rungs of a ladder).
Electron Energy Level Notes
• Energy levels are broken up into
sublevels:
• There are at least 4 possible types of
sublevels—given labels: s, p, d, or f
• Only a certain number of electrons may
exist in an energy level, but the number
varies. It can be determined by:
• # of electrons in level = 2 x (# of energy level)2
Electron Energy Level Notes
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Therefore:
energy level 1 = 2 (1)2 = 2
energy level 2 = 2 (2)2 = 8
energy level 3 = 18
energy level 4 = 32
etc...
Electron Energy Level Notes
• In each energy level, electrons fill sublevels in a
certain order (see p. 95)
• Level 1:
• only has one s sublevel (a spherical shape)
• 2 electrons may fit in this sublevel--each one has
an opposite “spin”, allowing them to take up the
same space
• Pauli exclusion principle—no more than 2
electrons may be found in the same orbital
(“orbital” means a particular location)
s-Orbital Image
Electron Energy Level Notes
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Level 2:
has two sublevels: s and p
2 electrons in s
there are 3 different p orbitals, and may hold 2
electrons each—6 total. (look at shape on p. 95-imagine how they can fit together)
• total of 8 overall in Level 2
p-Orbital Image
Electron Energy Level Notes
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Level 3:
has 3 sublevels: s, p, and d
2 electrons in s
6 electrons in p
there are 5 different d orbitals, and 2 electrons
can fit in each—total of 10. (look at picture of d
orbitals, imagine how they can fit together)
• total of 18
d-orbital notes
Electron Orbitals
Electron Energy Level Notes
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Level 4:
has 4 sublevels: s, p, d , and f
2 electrons in s
6 electrons in p
10 electrons in d
14 electrons in f (7 different orbitals for f)
total of 32
Image of orbitals
Electron Energy Level Notes
• The order that electrons fill up orbitals
does not follow the logical order of all 1’s,
then all 2’s, then all 3’s, etc.
• They follow the order found on pg. 98.
Order of Orbitals
Electron Energy Level Notes
• An easy way to remember this is to use
the periodic table--it is arranged to show
how these orbitals are filled.
Order of Orbitals—Periodic Table
Electron Energy Level Notes
• The first rule for filling orbitals is that only
one electron will be put in each orbital of a
sublevel until all of them are filled, and
after that, they may be paired up until the
sublevel is full.
• This is called Hund’s rule.
Quantum Model of atom
• The quantum model is more a concept
than something you have to calculate.
There are calculations, but for any atom
larger than hydrogen, these calculations
are very complex.
• It tells us where the electrons are located
around the atom and their energy level.
That is important because electron
location determines the behavior of the
electron and the atom.
Heisenburg Uncertainty Principle
• You cannot know an electrons velocity and
location at the same time.
• Determining where electron are and what
they are doing is very difficult
• electrons act like waves and particles at
the same time.
• They act a waves when we use them to
take pictures, like light pictures.
• They act like particles when they are used
to move objects.
We can use quantum numbers
to describe four important things
about the electron
• The principal quantum number indicates
overall energy and usually indicates distance
from the nucleus.
• The shape of its orbital (Azemuthal quantum
number)
• how that orbital is oriented with other orbitals
(Magnetic quantum number.)
• Another factor is the spin of the electron
(spin quantum number.)
The four quantum numbers.
• The first is N (Can be 1 or 2 or 3 and so
on.)
• The second is L the azemuthal quantum
number (0 to n-1) we substitute letters for
the value of L 0 s, 1 p, 2 d, 3 f
• the magnetic quantum number is M sub L.
It depends on L (goes from -L to L)
• Spin quantum number is M sub and has a
value of either +- 1/2
Wave Particle Duality
• At the level of the very small, waves are
not just waves, they are also particles.
• In addition, at the level of the very small,
particles are not just particles, they are
waves.
• Examples, your eyes are using the particle
nature of light to see and electrons create
a wave that can interfere with other
electron waves to make an image.