The%20bad%20news,%20good%20news%20and%20more%20bad%20news%20about%20elevated%20CO2%20levels%20in%20the%20atmosphere.

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• The bad news, good news and more bad news about
  elevated CO2 levels in the atmosphere.
• Bad news CO2 contributes to global warming.
• Good news The ocean is absorbing a good deal of
  this CO2, therefore slowing global warming.
• Bad news As the excess CO2 dissolves in the
  ocean, the ocean becomes more acidic, therefore
  threatening marine life that uses calcium
  carbonate to build its skeleton or shell. Think
  of coral, lobsters, star fish, and mollusks.

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• In experiment 2, we showed that CO2 comes from
  car exhaust as the engine burns gasoline making
  CO2 and water.
• When CO2 dissolves in water, we showed that it
  becomes carbonic acid. If this water is the
  ocean, this acid threatens the marine animals
  that use calcium carbonate to create their
  exoskeletons and shells.

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• There are many ways humans have damaged marine
  life for example, pollution, over fishing,
  dredging, and blasting are the obvious ways.
  Adding carbon dioxide to the atmosphere is a more
  hidden way of harming marine life a way that
  slowly dissolves their bodies.
• Many sea creatures build the shell or exoskeleton
  using calcium carbonate. This is how it can be
  dissolved
• First the carbon dioxide combines with water to
  make an acid called carbonic acid.
• CO2 H2O ? H2CO3
• Like most acids, the carbon acid releases a
  hydrogen ion (H). Its called an ion because it
  has a charge. In this case, its a plus one
  charge. The hydrogen ion (H) is the calling
  card of acids.
• H2CO3 ? HCO3- H
• The hydrogen ion attacks the solid calcium
  carbonate in the shell (or exoskeleton) causing
  the calcium to dissolve into the water. The
  CO32-(called the carbonate ion) combines with H
  to make whats called the bicarbonate ion (new
  name is hydrogen carbonate, which also dissolves
  in the water (ocean). The outcome is the marine
  animal looses its shell or exoskeleton and dies.
• HCO3- ? H CO32-
• CaCO3 2H CO32- ? Ca2(aq) 2HCO3-
• CaCO3 CO2 H2O ? Ca(HCO3)2
• CaCO3(s) H(aq)? Ca2(aq) HCO3-(aq)

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H
H
H
H

O
O-
O
O-
O
O-
O
O-
O
O-
C
C
C
C
C
Ca2
Ca2
Ca2
Ca2
Ca2
O-
O-
O-
O-
O-
O
O-
O
O-
O
O-
O
O-
O
O-
C
C
C
C
C
Ca2
Ca2
Ca2
Ca2
Ca2
O-
O-
O-
O-
O-
6
H
H
H
H
Ca2
6

4
Ca2
1
O
O-

H ions
C

2
O
O-

O
O-
O
O-
O
O-

O-
C
5
C
C
C

Ca2
Ca2
O-
Ca2


O-
O-
O-
3


O
O-
O
O-
O
O-
O
O-
O
O-
C
C
C
Ca2
C
C
Ca2
Ca2
Ca2
Ca2
O-
O-
O-
O-
O-
7
H
H
H
H
H
O
H
Ca2
Ca2
O-
O-
O-
C
C
O-
Ca2
O
O
O
O-
O
O-
O
O-
C
C
C
Ca2
Ca2
O-
O-
O-
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• To demonstrate that CO2 makes water acidic, we
  will bubble CO2 through water. Instead of the
  source of CO2 being your automobile, it will be
  yourself. Yes, you contribute to global warming
  and to the oceans acidity, too (but to a much
  lesser amount).
• We will detect the CO2 in two ways. Both ways
  show that the acidity of water increases when CO2
  is added. One way of showing it is by directly
  measuring pH. The other is similar to what we
  did in the car exhaust lab, but this time, you
  will provide the CO2.

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• The amount of CO2 that dissolves in water depends
  on the temperature of water. You know this from
  experience. If you open a soda can while warm,
  its likely to spray all over as the CO2
  hurriedly leaves the water to become a gas. If
  cold, more CO2 stays dissolved in the water as
  either CO2 or as H2CO3.
• We are going to blow into a beaker of ice water
  using some tubing attached to an air stone. The
  concentration of CO2 in air from our lungs is
  about 4 (thats about 4 CO2 molecules (with the
  remaining 100) being water, oxygen, and nitrogen
  molecules), 5 water (H2O) molecules, 15 oxygen
  (O2) molecules, and 76 nitrogen molecules (N2).
  With the car exhaust, CO2 concentration was about
  12 (12 CO2, 75 nitrogen molecules, and 13 H2O.

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• CH3(CH2)6CH3 12.5 O2 ? 8CO2 9H2O
• 12.5 to x 20 to 80 ( 4 x 12.5)50
• 50 molecules N2 8CO2 9H2O