Download 1. Dehydration Synthesis 2. Fermentation

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Millions of molecules = Millions of
reactions
…But we’ll just look at a few, eh?
For each one:
1. Focus on what is happening.
2. Make sure you can ID reactants and
Products.
• Unit 15: Organic Chemistry
• Lesson 15.3: Organic Reactions
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Etherification
1. Dehydration Synthesis
Requires two alcohols.
Uses a dehydrating agent (or enzyme) to
remove an H from one hydroxyl and an OH
from the other. This becomes water.
Joining two (or more) molecules together
by removing water from functional groups.
Two kinds for you:
1. Etherification
2. Esterification
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Esterification
2. Fermentation
Requires an alcohol and a carboxylic acid.
Uses a dehydrating agent (or enzyme) to remove an H
from the carboxyl and an OH from the hydroxyl. This
becomes water.
Naming esters “(alcohol)-yl (acid)-oate”
Many kinds. You need to know yeast fermentation:
Use of an enzyme (“zymase”) in yeast cells to turn
sugars (carbohydrates—from grains) into ethanol and
carbon dioxide.
Very complex reaction mechanism
The most commercially important organic reaction(?).
Yeast die at %13 ethanol concentration. Have to
distill higher concentrations
Zymase
C6H12O6 -------------> 2 CH3CH2OH + 2 CO2
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3. Saponification
4. Polymerization
Uses a glycerol ester
(a “fat”) and NaOH.
Dissolve the fat in
ethanol. Mix in the
NaOH.
Heat the mixture
slowly.
Evaporate off the
alcohol.
Add NaCl to
precipitate out the
soap.
Dry it off.
The joining of many identical subunits (monomers) into
a huge molecule (a polymer).
General Formula:
Three kinds of polymers for you:
1. Addition Polymers
2. Condensation Polymers
3. Rubber
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Addition Polymerization
Condensation Polymerization
The monomers have a double bond, which is opened
with a catalyst.
The unpaired electrons in the monomers bond with other
monomers.
This is how most commercial plastics are made.
Polyvinylchloride (PVC):
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Dehydration synthesis removes water from the ends of
monomers, joining them together.
Water is produced as a by product.
How all biological polymers (proteins, nucleic acids,
cellulose, starch, etc.) are produced
Polyester:
Polystyrene (aka “styrofoam”):
styrofoam ):
Polytetraflouroethane (aka
“teflon”):
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Rubber
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So, what should you be able to do?
Addition polymerization.
The initial polymerization makes a sticky, easily
separated molecule.
Vulcanization:
Addition of sulfur
strengthens the rubber
polymers by forming
cross-linkages.
Discovered by
Charles Goodyear in 1839
Vulcanized rubber burns, producing CO, CO2, and
SO2(boo!)
1. Recognize a reaction when you see it.
2. Identify all products and reactants.
3. Determine the products of a particular
reaction.
4 Determine the reactants needed to make a
4.
particular product.
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Any
Questions
?
BUT WAIT….
Charles Goodyear
(1800 –1860)
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