Environmental Chemistry

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Environmental Chemistry

• I believe that global warming is a myth. And so,
  therefore, I have no conscience problems at all
  and I'm going to buy a Suburban next time.
  -Jerry Falwell
• Global warming is not a conqueror to kneel
  before - but a challenge to rise to. A challenge
  we must rise to. -Joe Lieberman-

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Quiz 10

• Please give the Lewis structure, the electron
  pairs in the structure and the shape of the
  following molecules.
• NF3
• SO2

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King Henry Died Drinking Chocolate Milk
Or Units Dr Freeman Assumed You Would Ask Him
About If You Didnt Know.
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King Henry Died Drinking Chocolate Milk
Or Units Dr Freeman Assumed You Would Ask Him
About If You Didnt Know.
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We can use the VSEPR model to allow us to predict
the shape of other molecules.
Other predictions can be made based on other
electron pair arrangements .
3.3
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Molecular geometry and absorption of IR radiation
Molecular vibrations in CO2. Each spring
represents a CO bond. (a) no net change in
dipole - no IR absorption. (b, c, d) see a net
change in dipole (charge distribution), so
these account for IR absorption
3.4
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The infrared spectrum for CO2
As IR radiation is absorbed, the amount of
radiation that makes it through the sample is
reduced
3.4
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Dipoles

• A dipole is when electron density is unequally
  distributed between atoms.
• When two atoms differ in how much they would
  like electrons they form a dipole.

-d
d
d
-d
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Increasing need for electrons
Electronegativity Patterns in the Periodic table
Increasing need for electrons
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Dipoles

• A dipole is when electron density is unequally
  distributed between atoms.
• When two atoms differ in how much they would
  like electrons they form a dipole.

-d
d
d
-d
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The infrared spectrum for CO2
Wavenumber (cm-1) 10,000
wavelength (mm)
3.4
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The carbon cycle
3.5
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Keeping track of Carbon

• We need some way to count they amount of carbon
  that we see
• The Mole is a useful unit of measure that helps
  us.

Gustav Mützel
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Mole SI definition the number equal to the
number of carbon atoms in exactly 12 g of pure
C-12.
Atomic number
Avogadros number is 6.022 x 1023
Mass number
A mole of atoms of any element has a mass (in
grams) equal to the atomic mass of the element in
amu.
The carbon cycle
3.7