Download Characteristics of Waves

Chapter 4
Electrons
In Atoms
Properties of Light
 ___________________:
a form of
energy that exhibits wavelike
behavior as it travels through space.
(ex. Visible light, x-rays, UV, IR, radio)
 ____________________: all forms of
electromagnetic radiation together
make up the spectrum.
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Properties of Light
Characteristics of Waves
 There

are 4 main characteristics of
waves:
1) ___________: The height of the
wave measured from it’s origin to it’s
peak. When you increase the
intensity, or brightness of light, you
are increasing it’s amplitude.
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Characteristics of Waves
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Characteristics of Waves
 2)________________:
the distance
between corresponding points on
adjacent waves. Wavelength is
designated by the Greek symbol
__________.
Wavelength = ___
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Characteristics of Waves
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Characteristics of Waves
 3)
___________: the number of
waves that pass a given point in a
specific time. Measured in cycles per
second (cycle/second, or s-1) The SI
unit for this is Hertz. 1.0 Hz = 1.0 s-1
Frequency is designated by the Greek
symbol ___. Frequency = ____
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Characteristics of Waves
Characteristics of Waves
 4)
_________: the speed of
light is constant. It is rounded
to _________ m/s. The
speed of light is represented
by the letter ____.
___ = λυ
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The Photoelectric Effect
 Refers to the emission of _________
from a metal when light shines on the
metal.
 __________: the minimum amount of
energy that can be lost or gained by an
atom
 ____________, a German physicist
studied quanta of light and found:
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The Photoelectric Effect
E = _____
Where h is Plank’s
Constant and has a value
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of 6.6262 x 10 Js
(energy)
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The Photoelectric Effect
Einstein expanded upon this to propose that
light has a ______________, acting as a
_______ under some circumstances and a
____________ under others.
__________: a particle of electromagnetic
radiation having zero mass and carrying a
quantum of energy.
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Line Emission Spectrum
______________: the lowest energy
state of an atom
_____________: a state in which an
atom has a higher potential energy
than it has in it’s ground state.
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Line Emission Spectrum
_____________________: a graph that
indicates the degree to which a
substance emits radiant energy with
respect to ______________.
______________________: the emission
of a continuous range of frequencies
of electromagnetic radiation.
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H Emission Spectrum
_____________: a Danish physicist who
proposed a hydrogen-atom model
that linked the atom’s electron to
photon emission. (electrons circle the
nucleus in “_______”)
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H Emission Spectrum
Emission Line Spectrum: a graph that
indicates the degree to which a
substance emits radiant energy with
respect to wavelenth.
Continuous Spectrum: the emission of
a continuous range of frequencies of
electromagnetic radiation.
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H Emission Spectrum
Emission Line Spectrum: a graph that
indicates the degree to which a
substance emits radiant energy with
respect to wavelenth.
Continuous Spectrum: the emission of
a continuous range of frequencies of
electromagnetic radiation.
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The Quantum Model
____________________________: states that
it is impossible to determine
simultaneously both the ___________ and
_______________ of an electron or any
other particle.
___________________: describes
mathematically the wave properties of
electrons and other very small particles.
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The Quantum Model
______________________: specify the
properties of atomic orbitals and the
properties of electrons in orbitals.
Quantum numbers were developed based
on the ____________________, developed
by Austrian physicist Erwin Shrödenger.
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The Quantum Model
__________________________: indicates the
main energy level occupied by the
electron. Values are positive integers only
(1, 2, 3, 4 with 1 being the lowest energy
level closest to the nucleus)
_______________________: indicates
the shape of the orbital. Values are 0,
1…n-1)
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The Quantum Model
l=0=s
l=1=p
l=2=d
l=3=f
The Quantum Model
Magnetic Quantum Number (m): indicates
the orientation of an orbital around the
nucleus. Values, including zero, are –l to
+l
l = 0 = s orbital has only one orientation (sphere)
l = 1 = p has three orientations
l = 2 = d has five orientations
l = 3 = f has seven orientations
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The Quantum Model
The Quantum Model
The Quantum Model
The Quantum Model
________________________: indicates the
two fundamental spin states of an electron
in an orbital. Values are +1/2 or -1/2.
______________________: the arrangement
of electrons in an atom.
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Orbital Filling Diagrams
There are ____________, named after the
scientists that discovered them, that
govern the filling of these orbitals with
electrons…
1)
The ________________: an electrons
occupies the lowest energy orbital
that can receive it.
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Orbital Filling Diagrams
2) The ________________________: no two
electrons in the atom can have the same
set of four quantum numbers.
3) _______________: Electrons occupy equal
energy orbitals so that a maximum
numbered of unpaired electrons results,
and all e- in singly occupied orbitals
must have the same spin.
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Orbital Filling Diagrams
When using this form, each electron is
designated as an _______ ________
pointing up or down to show opposite
spins. Each orbital is designated with a
labeled line: ____ or __ __ __
1s
2p
____________lines show multiple orbitals (1
for s, 3 for p, 5 for d)
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Orbital Filling Diagrams
Orbitals fill going _____________ each
period (_____) on the periodic table,
from the lowest energy level up.
(Aufbau). Don’t forget, when they pair,
they have ____________ (Pauli), but they
won’t pair until each available orbital
has an unpaired electron in it first
(Hund)
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Orbital Filling Diagrams
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Orbital Filling Diagrams
_____________, with one electron, would have an
orbital filling diagram of:

1s
__________, with 2 electrons, would be:

1s
Now your at the end of the first period, start again
in the 2nd period with 2s…
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Orbital Filling Diagrams
Lithium:
 
1s 2s
Be:
 
1s 2s
B:
 
 _ _
1s 2s
2p
Orbital Filling Diagrams
Which of these would be correct for oxygen (with 8 e-):
O:
 
  ?
1s 2s
2p
OR
 
  
1s 2s
2p
____________ is correct, the _________ example violates
the Pauli Exclusion Principle.
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Practice
Write the orbital filling notation for the
following elements:
1) Be:_________________________
2) F:__________________________
3) Ar:_________________________
4) Cu:_________________________
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Electron Configurations
Now your ready to write electron configurations. These are simply the
orbital diagrams written out with superscripts:
Lithium:
 
1s 2s would be written out as 1s2 2s1
Be:
 
1s 2s would be written out as 1s2 2s2
B:
 
 _ _
1s 2s
2p
would be written out as 1s22s22p1
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Practice
Write the electron configuration for the
following elements:
5) Mg:________________________
6) N:_________________________
7) Cr:________________________
8) Cl:________________________
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Electron Configurations
___________________: refers to an outer main
energy level occupied by eight e

Once a __________ is complete at the end of a
period, you can write subsequent
configurations as having the _______ of the
___________ with the additional ___________
electrons.
Sodium Na would have a noble gas notation
of:
Ne3s1
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Practice
Write the noble gas notation for the following
elements:
9) Na:_________________________
10) Sb:_________________________
11) Y:__________________________
12) F:__________________________
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Ch. 4
The
End
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