Download Unit 4 Chemistry of Carbon

Unit 4 Chemistry of Carbon
Organic Chemistry studies the compounds of the element carbon
In many of these compounds carbon is found bonded to
Hydrogen, oxygen, nitrogen, phosphorus, sulfur, and halogens
Contrasting organic and inorganic compounds
Type of Compound
Organic
Type of bonds
Covalent
Melting point
Low
Boiling point
Low
Combustibility
Burns easily
Number of molecules
Millions
Water solubility
Mostly nonpolar (insoluble)
Conductivity
Nonelectrolytes
Elements found in organic compounds
Element
Lewis dot
structure
Carbon
C
Hydrogen
# of bonds
Inorganic
Ionic
High
High
Does not burn easily
Thousands
Most are polar or ionic (soluble)
Electrolytes
Bond arrangements
H
Oxygen
O
Sulfur
S
Nitrogen
Halogens
F, Cl, Br, I
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N
Cl
1
Hydrocarbons: The simplest carbon compounds (Composed of only hydrogen and carbon.)
The main source of hydrocarbons is oil.
Importance of hydrocarbons:
1. Energy
Small hydrocarbons (1-4 C’s) are gases, medium sized (5-17C’s) hydrocarbons are liquids, and big
hydrocarbons (over 17 C’s) are solids like waxes. They burn well :
CxHy +O2 Æ H2O + CO2 + energy (calories)
There is a lot of energy given off when this reaction occurs. Liquid hydrocarbons are excellent fuels for
cars and trucks or any other transportation form.
2. Building blocks for every day materials
We have become dependent on plastics or, to use the chemical, term polymers. From car parts to fabrics to
packaging, it is hard to find anything that does not contain plastics. Also the building blocks for many
pharmaceutical drugs come from hydrocarbons.
General
formula
Alkanes
CnH2n+2
saturated
Alkenes
Example
Full Structural formula
H
CnH2n
H
H
H
C
C
C
H
H
H
H
Condensed structural
formula
H
Name
CH3CH2CH3
propane
CH2CHCH3
propene
CHCCH3
propyne
H
unsaturated
C
C
C
H
H
H
H
H
Alkynes
CnH2n-2
unsaturated
H
C
C
C
H
H
Hydrocarbons can also have a ring structure: which is usually indicated by having cyclo in its name
Benzene: (A cyclic structure that doesn’t use the phrase cyclo – because it is “special”)
H
C
HC
CH
HC
CH
C
H
It has an aromatic structure, which is extremely stable and unreactive. It is unsaturated, but behaves as if it
is saturated due to it’s high stability.
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2
Types of Carbon
Primary
1o Bonded to only 1
other carbon
Secondary
2 o Bonded to 2
other carbons
Tertiary
3 o Bonded to 3
other carbons
Quarternary 4 o Bonded to 4
other carbons
H
H
CH3
H
H
H
H
C
C
C
C
C
C
H
CH3
H
H
CH3
H
H
Alkanes
Name
Molecular
Full Structural formula
Condensed structural formula
Formula
CH4
H
Methane
Ethane
Propane
Butane
Pentane
Hexane
Heptane
Octane
Nonane
Decane
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CH4
C2H6
C3H8
C4H10
C5H12
C6H14
C7H16
C8H18
C9H20
C10H22
H
H
H
H
H
H
H
H
H
H
C
H
H
H
H
C
C
H
H
H
H
H
H
C
C
C
H
H
H
H
H
H
H
H
C
C
C
C
CH3CH3
CH3CH2CH3
CH3CH2CH2CH3
H
Or
CH3(CH2)2CH3
CH3CH2CH2CH3
H
H
H
H
H
H
H
H
H
C
C
C
C
C
H
H
H
H
H
H
H
H
C
C
C
H
H
H
H
C
H
Or
H
H
H
CH3(CH2)3CH3
CH3CH2CH2CH2CH2CH3
C
C
C
H
H
H
H
H
H
C
C
C
H
H
H
H
H
H
H
H
H
H
H
H
C
C
C
C
C
C
C
C
H
H
H
H
H
H
H
H
H
H
H
H
H
H H
H H
H
C
C
C
C
C
C
C
C
H
H
H
H
H H H H H H H
H H H H H H H
H
C
C
C
C
C
C
C
C
C
C
H
H
H
H
H
H
H
H
H
H
H
Or
H
H
H
CH3(CH2)4CH3
CH3CH2CH2CH2CH2CH2CH2CH3
C
C
C
H
H
H
Or
H
C
CH3(CH2)5CH3
CH3(CH2)6CH3
CH3(CH2)7CH3
H
CH3(CH2)8CH3
H
3
Side Chains and Side Groups (Subtituents)
Name
Full Structure
Example
H
methyl
C
H
H
H
H H
H
C
C
H
H
H
isopropyl
fluoro
C
C
C
H
H
H
H
4-methyloctane
H
H
CH3H
H
ethyl
propyl
H
Name
2- methylpropane
H
H
H
C
C
C
H
H
H
H
H
C
C
C
H
H
H
H
C
H
H
C
H
H
H
H
C
C
C
H
H
H
H
H
H
H
C
C
C
C
C
H
H
H
H
H
CH3CH2CH2CH2CH2CHCH2CH2CH2CH3
5-propyldecane
CH2CH2CH3
4-isopropylheptane
CH3
H
H
H
H
H
H
C
C
C
H
H
H
F
H
C
C
H
CH3
H
H
H
C
C
C
H
H
H
H
H
C
C
H
H
Cl
Cl
H
Fluoroethane
F
Chloromethane
H
chloro
H
C
H
H
bromo
Br
H
H
Br H
C
C
H
iodo
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I
H
2-bromopropane
C
H
H
H
H
H
H
H
C
C
C
C
H
H
H
H
1-iodobutane
I
4
Classes of Compounds and Functional Groups
Class of
compound name
Alkane
Functional group
C
C
Functional group
description
Single bonded
carbons
Example Name
Ethane
H
Alkene
C
Double bonded
carbons
C
H
H
C
C
H
H
H
Ethene
H
H
C
C
H
Alkyne
C
Aromatic
C
C
C
C
Triple bonded
carbon atoms
Aromatic ring of
six carbons
H
Ethyne
H
C
C
Benzene
H
H
H
C
C
C
H
C
C
C
C
C
C
H
H
H
Alcohol
O
H
hydroxyl
Methanol
H 3C
Ether
Oxygen bonded
to 2 carbons
O
Methoxymethane
O
H 3C
Aldehyde
C
carbonyl
O
OH
O
CH3
Methanal
O
C
H
H3C
Ketone
Carbonyl between
2 carbons
O
C
H
2-propanone
O
C
H3C
Carboxylic acid
carboxyl
O
C
CH3
Ethanoic acid
O
C
OH
H3C
Ester
Carboxyl group
with H
replaced by C
O
C
Thiol
O
S
O
C
O
CH3
Methanethiol
H3C
Amine
OH
Methylmethanoate
H 3C
H
C
S
H
Amino methane
H
N
H 3C
Amide
C
3/08
N
H
O
N
5
General naming Rules for organic compounds:
For most compounds there are no spaces (there are exceptions) (Yes, these can get very long!)
The following will give you a general idea of how to name simple organic compounds.
1. Find any functional groups present. That functional group will identify the ending in the name of the
compound, it will also help you to determine the main chain. (ie. ane, ene, one, anol etc)
2. Find the longest continuous hydrocarbon chain which includes any functional groups. That main chain
will identify the length of the main chain name used near the end of the name. (ie. 6 C’s in uses hex.)
3a) If there are no functional groups present (all single bonds and no O, N or sulfur, but there may be
halogens) then: Number the carbons in this chain from the end that will give the side chains the smallest
total number.
3b) If there is a functional group (other than halogens) then the functional group gets the lowest possible
number and the direction of counting is determined by that.
4. Number the side chains with the number of the carbon they are attached to, followed by a hyphen and
then the name of the side chain. (i.e. 2-methyl)
5. If there are more than one of the same side chain use the numbers (in numerical order) separated by
commas and then use di, tri, tetra, penta, etc. (2,2,3-trimethyl) Remember that each side chain must
have a number to tell where it is!
6. Number the functional groups by placing the number then a hyphen in front of the main chain length
name. (ie.2-pentanone)
7. If there are more than one kind of side chain or functional group put them in alphabetical order with a
hyphen separating any number and letter. (4-ethy-3-methyl)
8. Beware that some functional groups never require a number since they can only be in position 1 (ie
aldehydes)
9. Rarely, the number need not be provided because the size of the carbon chain length limits the available
positions of the functional groups. (ie. butanone not 2-butanone)
10. Some compounds have a cyclic structure, for most of those we add in the term cyclo in front of the
main chain name and the numbering starts, by following the rule that functional groups get lowest
numbers and then total number should be the lowest. (ie 2-methyl-1-cyclobutanol)
General rules for drawing Organic compounds:
1. Draw the main chain carbons first, a straight line is the easiest.
2. Attach any functional groups to appropriate positions. (Usually from left to right is easiest)
3. Attach all side chains to appropriate positions. (Determined by your functional group placement)
4. Add in appropriate number of hydrogens. (Recall the HONC rule - each C needs 4 bonds.)
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6
Alkanes
H
H
H
Cl H
H
H
C
C
C
C
C
C
H
H
H
H
H
H
H
H
H
HC HHC H
H
H H
HC C C C C
H
H H H
HC H
H
H
H H H H H H H H
HC C C C C C C C H
H H H H
H H H
HC H
H
H
C H
H H
C C C H
H H H
CH2CH3
CH3CH2CHCH2CH2CHCH3
CH3
H
H
H
H
H
C
C
C
H
H
H
C
CH3
H
H
H
C
C
C
C
H
H
H
H
F
H
Cl
CH3CH2CCH2CHCH2CH3
CH(CH3)2
CH2CH2CH3
CH3 CH3
CH3CH2CH2CCH2CHCH2CH3
CH(CH3)2
3-fluoro-2-methylhexane
4-ethyl-3-methylheptane
Octane
1-bromo-2-methylcyclobutane
2,2,4-trimethylpentane (isooctane)
Octane and 2,2,4-trimethylpentane both have the same formula C8H18 (they are isomers of each other). The difference is that
2,2,4-trimethylpentane is more branched. The branched chained molecules are better for gasoline mixtures. Straight chain
molecules ignite too explosively causing “knocking”. Branched molecules burn more smoothly. Isooctane has an octane number
of 100 because of its anti-knocking properties. Heptane has an octane rating of 0. It has poor anti-knocking quality. A 95 octane
rating would be like having 95% isooctane and 5% heptane. For diesel engines, just the opposite is best. Diesel engines work
better on less branched molecules. Diesel engines run on hexadecane, 16-carbon molecules.
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7
Physical properties:
Boiling point increases with an increase in molar mass or increase in the number of carbon atoms.
Number of C atoms
Uses
Boiling point
1-4
Natural gas
< 30
5-12
Gasoline
30-200
12-16
Jet fuel
200-250
15-18
Diesel
250-350
18-25
Motor oil
350-450
>25
Tar, asphalt
Solid, does not boil
Boiling point decreases with an increase in branching.
Very low solubility in water as they are nonpolar.
Functional Groups
Groups of atoms or single atoms can be added to hydrocarbon chains that greatly influence the physical and
chemical properties of these molecules. Double and triple bonds are functional groups. Also, many
functional groups contain oxygen or nitrogen.
Alkenes and Alkynes
Importance of Alkenes and Alkynes:
Alkenes used to synthesize a wide variety of polymers. Alkynes, especially ethyne is a specialized fuel.
Naming:
Alkenes and alkynes are named the same way with the longest chain that contains
double bond, change ane to ene,
triple bond, change ane to yne.
The double or triple bond gets the lowest possible number, and is only numbered from the start of the bond
Remember, each carbon can only have 4 bonds. These are referred to as unsaturated hydrocarbons.
H
H
H
H
C
C
C
H
H
H
C
C
H
H
H
H
H
C
C
H
C
C
H
H
H
H
H
H
H
C
H
C
C
H
H
C
CH3
H
H
H
C
C
C
C
H
H
H
H
H
H
H
H
C
C
H
H
H
C
C
C
H
H
CH2CH3
CH2CHCHCH2CH2CHCH3
CH2CH2CH3
4-methyl-3-heptene
3/08
HC
CH
2-butyne
8
Aromatic Hydrocarbons
Importance of aromatic compounds:
Aromatic compounds contain a benzene ring. They are very stable compounds and react in many ways.
They are found in fuels, biological molecules, plastics, drugs, explosives, foods, flavors, and dyes just to
name a few. They tend to have a characteristic odor or aroma, hence the name aromatic.
Structure and Naming:
Functional Group: Aromatic ring
What you need to know:
1) What it looks like: a 6 membered ring with alternating single and double bonds.
2) It is very stable
3) It is unsaturated but the stability allows it to behave as a saturated hydrocarbon.
CH3
OH
H
C
HC
CH
HC
C
C
CH
C
H
HC
CH
HC
CH
HC
CH
HC
CH
C
H
C
H
O
O
OH
H3C
HC
C
C
C
OH
NO2
C
H
Acetylsalicylic Acid
CH
HC
H
C N
C
HC
CH
HC
Salicylic Acid
HC
C
CH3
O
CH
CH3
CH
HC
C
HC
H
C
O
C
H
C
H
CH
C
O
HO
N-Acetyl-para-aminophenol
(Tylenol)
Cinnamaldehyde
C
CH
H
C
O
Vanillin
CH3
OH
HO
HO
CH
C
HC
CH3 C CH3
O
CH3
OH
OH
Pelargonidin
This molecule is responsible for the red
color we see in raspberries and
strawberries.
3/08
CH
C
CH
C
H
HO
C
HC
OH
C
NO2
C
C
C
HC
C
O2N
O
O
C
HC
CH3
O
2-tert-butyl-4-methoxyphenol
Also called BHA an antioxidant. Molecules in food cause fat molecules to oxidize
or rot or break down into smaller molecules and become rancid. BHA attacks the
molecules that oxidize the food before they can attack the food.
9
Alcohols
Importance of alcohols:
Fermentation: Yeast ferments sugars found in grains like corn and barley or fruits like grapes and apples to
produce ethanol.
Combustion: In some ways our bodies are like the engines in our cars. Both can combust or burn alcohol to
produce carbon dioxide and water and energy. In our bodies the reaction is more complicated but the result
is the same
Ethanol + Oxygen Æ carbon dioxide + water
CH3CH2OH
+ O2 Æ CO2 + H2O
Caloric value: Calories/gram
Fat = 9
Alcohol = 7 Carbohydrates = 4
Protein = 4
Ethanol Economics:
Structure and Naming:
Functional group:
-OH
General Formula:
R-OH
Three types of alcohols:
H
H
H
OH
C
C
C
H
H
H
hydroxyl group
ROH
H
H
1-propanol
Primary 1o
The hydroxyl (OH) group is attached
to a primary or methyl carbon
H
H
H
C
C
C
H
OH H
H
H
2-propanol
Secondary 2 o
The hydroxyl (OH) group is
attached to a secondary carbon
H
CH3H
C
C
H
OH H
C
H
2-methyl-1-propanol
Tertiary 3 o
The hydroxyl (OH) group is
attached to a tertiary carbon
1. Change the name of the longest chain that contains the –OH from ane to ol and number the chain giving
the OH the lowest number.
H
CH3OH
H
and
H
C
C
H
H
H
H
OH H
H
H
C
C
C
C
C
C
H
H
H
H
H
H
2-propanol
3/08
H
OH
H
H
H
H
H
H
H
H
H
H
OH
C
C
C
C
C
C
C
C
C
H
H
H
H
H
H
H
H
H
CH3H
H
CH3H
H
H
C
C
C
C
C
C
H
H
H
OH CH3H
H
C
H
H
CH3
2-methyl-3-pentanol
10
Ethers
Importance of ethers
They have been used as anesthetics for many years. They are very volatile and explosive.
Structure and Naming:
Ethers are similar to alcohols in that they contain an oxygen with 2 single bonds. They differ in that the
oxygen is not bonded to a hydrogen but to 2 carbons.
Functional group:
General Formula:
COC
R-O-R’
1. Name the longest continuous hydrocarbon chain with its normal alkane name.
2. Change the name of the other, shorter hydrocarbon chain, with the oxygen, from its normal alkane
name from ane to oxy. It is treated as a side chain with a number.
H
H
H
C
O
H
H
C
H
H
H
H
H
C
C
H
H
O
H
H
H
H
H
OH
C
C
C
C
C
C
H
H
H
H
H
H
H
H
C
C
H
H
O
CH3
H
H 3C
C
H
H
H
C
C
C
H
H
H
H
CH3
O
CH3
MTBE fuel additive used to increase oxygen in the
fuel for cleaner burning
.
2-methoxybutane
3-methyl-2-ethoxy butane
Thiols
Importance of thiols:
These molecules have a very strong odor and are found in perm solutions, foods, coffee and skunks!
Structure and Naming:
These molecules are similar to alcohols but the oxygen is replaced by a sulfur with 2 bonds
Functional group:
-SH
sulfhydryl
General Formula:
R-S-H
Name the same as alcohols but use the suffix thiol instead of just ol.
CH3CH2SH
CH3SH
Added to natural gas to detect leaks through odor
Found in oysters and cheese
H
S
H
H
H
C
C
C
H
H
H
H
H
Onions
O
SH
C
C
H2
C
H
2-furymethanethiol coffee scent.
3/08
S
C
C
C
H
H
H
2-propene-1-thiol Garlic
HC
HC
H
H
H
S
H
H
CH3
C
C
C
H
H
H
CH3
3-methylbutane-1-thiol skunk scent
11
Aldehydes
Importance of aldehydes:
Aldehydes are quite reactive due to the oxygen atom and are used to make many other types of molecules.
Vanillin (see below) contains 3 functional groups and is responsible for the flavor of vanilla. Thomas
Jefferson introduced this flavor to the United States.
Structure and Naming:
Aldehydes have a carbon double bonded to an oxygen at the end of a hydrocarbon chain
O
O
Functional group:
O
C
is called the carbonyl group
CH
CH
General Formula:
R
RCHO
Change the name of the longest continuous hydrocarbon chain that has the CHO from ane to al. There
is no number since the functional group is always on the end or first carbon.
O
H
O
Very toxic. Used to preserve specimens.
Ethanol is oxidized in the liver into this
H
C Kills bacteria.
H
C
C molecule which is somewhat responsible
for the “hangover”
H
H
H
Acetaldehyde
Formaldehyde
CH3 O
O
C
O
H
HO
Benzaldehyde responsible for the flavor of almonds
H
Vanillin (notice 3 functional groups and benzene)
Butanal
2-methylbutanal
Ketones
Importance of ketones: Acetone is found in nail polish remover, found in many flavorings
O
O
Structure and Naming:
O
C
Functional group:
is called the carbonyl group
C
C
C
C
R'
General Formula: R
RCOR
1. Change the ending of the name the longest hydrocarbon chain that contains the carbonyl from ane to one.
2. Number the carbon with the carbonyl so that it has the lowest number.
O
O
Acetone found in nail polish
remover.
Very flammable.
H2
H2
H 3C
C
C
C
CH3
Produced by bacteria.
Found in the smell of
H 3C
C
C
CH3
armpits and unwashed feet.
Butanedione: the flavor of butter and margarine.
O
C
CH3
O
2-methyl-3-pentanone
3/08
H 3C
butanone
5-methyl-3-hexanone
12
Carboxylic acids
Importance of Carboxylic acids:
These are weak acids. The hydrogen in the carboxyl group can ionize a little bit in aqueous solution. They
are found in all types of food, giving a sour taste.
Structure and Naming:
The functional group is a combination of a carbonyl and a hydroxyl or a carboxyl.
O
Functional group:
called a Carboxyl group
OH
C
O
General Formula:
RCOOH
C
R
OH
Esters are named with 2 words
1. Change the ending of the name of the longest chain that contains the carboxyl group from ane to oic
acid. There is no number since the carboxyl group is always on the end. (It always starts at position 1)
Lactic Acid Found in milk, and
Alcohol is oxidized to this and
O
O
that
is
why
cheap
wines
taste
like
pickles
Responsible for sore
H
CH
CH
3
vinegar. Certain bacteria break
OH muscles from heavy activity or
H C C O H down the sugar maltose in dough
heavy drinking. when
OH
into
acetic
acid,
giving
sour
sugars.breakdown.
H
dough.
Acetic acid: found in vinegar.
O
C
OH
Kills bacteria and is used as a
preservative in foods, cosmetics
and toothpaste.
CH3CH2COOH
Benzoic Acid
Injected by stinging ants
Methanoic acid . Also called formic acid.
Pentanoic acid
2-methylhexanoic acid
3/08
13
Esters
Importance of esters
The food industry relies heavily on esters for the flavoring of food. Many natural flavors are due to esters.
Structure and Naming:
Esters are similar to carboxylic acids in that they contain 2 oxygens one with a single bond and one with a
double bond. They differ in that the functional group is not on the end of the molecule.
O
Functional group:
C
O
O
General Formula:
RCOOR
C
O
R'
R
Esters are named with 2 words
1. The 2nd word is made by changing the ending of the name the longest hydrocarbon chain that contains
the carbonyl from ane to anoate
2. The 1st word is the alkyl group that is attached to the single bonded oxygen. It is named like a side
chain- but there is no number.
3. There is no number since the carboxyl group is always on the end. (It always starts at position 1)
O
O
H 3C
C
O
CH3
CH3CH2CH2CH2CH2CH2CH2
H
CH3COOCH2CH2CH2CH2CH3.
(This is responsible for the flavor of bananas.)
H C
H
H H
H
H O
O
C
CH3
H
C C C C C O C H
H
H
H H
HC H
H
amyl acetate
Methyl salicylate: This molecule
is responsible for the flavor of
O
wintergreen. is a mild irritant
when rubbed on the skin. This
induces a brief and minor
O inflammation of the skin
which delivers more blood and
OH
more heat to the skin and
subcutaneous regions such as muscles. This is
why methyl salicylate is an active ingredient in
many liniments.
Recently methyl salicylate has been shown to be an
anti-aphrodisiac in moths. During mating, a male
moth transfers a sperm packet, which contains sperm
and nutrients, into the body of the female. During
the next 24 - 48 hours the female will lay eggs which
are fertilized by this male's sperm. In order to
discourage other males from mating with the female,
the sperm packet is also laced with methyl
salicylate. It has been observed that other males will
approach a recently mated female, but are repelled
by the Oil of Wintergreen. It appears that the
females do not become attractive again until about 5
days after their first mating. The first male therefore
derives a reproductive advantage in having more of
his offspring in the next generation.
Propyl ethanoate
Butyl 3-methylpentanoate
H 3C
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Amines
Importance of amines
Amines can accept a hydrogen which makes them weak organic bases. They are an important part of
amino acids. They generally smell bad.
Structure and Naming:
Amines have all single bonds and contain a nitrogen.
H
Functional group:
Called the amino group
H
N
H
R
N
H RNH2
General Formula:
1. Add amino to the name of the longest hydrocarbon chain with the amino group and indicate its position
with the smallest possible number.
H
NH2CH2CH2CH2CH2CH2NH2
Putrescine: The horrible odor from rotting flesh
H N CH2CH3
H H H H H H
HC C C C C N H
H
H H H
HC H
H
H2
C
CH
CH3
H3C
N
CH3
Responsible for the odor of rotting fish. When
lemon is squeezed onto cooked fish the citric
acid in the lemon neutralizes the amine
(organic base) and forms a salt getting rid of
the fishy taste.
Trimethylamine
H2
C
CH3
H2
C
H
N
CH3
NH2
Amphetamine
Methamphetamine Also called “speed”.
This molecule
absorbs UV light
HO
C
NH2
from the sun and is
found in sun block.
para-aminobenzoic acid Also called PABA
O
2-aminopentane
It is both an amine and a carboxylic acid.
Amides
Importance of amides
Amides are neutral. They are an important part of proteins.
Structure and Naming: (you will not name the amides, just recognize the structure, class functional group)
O
Amide
Functional group:
C
N
O
RCONH2
General Formula:
R
H O
H N
CH
Methanamide
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C
N
R'
H
C
H O
H N
CCH3
Ethanamide
O
H
N CH2CH3
N-ethylmethanamide
15
Polymers
Polymers are enormous molecules made up of repeating units called monomers. “Mer” simply means unit.
Just like a train is a long chain of repeating similar train cars hooked together, a polymer is a long chain of
similar molecules chemically hooked together. You wear polymers, you drive with polymers, you work
with polymers, you chew polymers. They are everywhere. The properties of polymers depends on the
individual repeating units and how they are hooked together. Polymers can be “man made” but are also
found in nature. Protein is a polymer.
Polyethylene is a very common plastic. It is found in bags, plastic wrap and milk bottles. If you have seen
the triangle symbol with HDPE, you are using polyethylene.
Here is how it is made:
H
H
C
H
Ethene (ethylene) is hooked together:
H
H
+
C
C
H
+
C
H
H
H
H
C
etc. Æ
C
H
H
H
H
H
H
H
H
C
C
C
C
C
C
H
H
H
H
H
H
This chain can be hundreds or thousands of ethene units. The chains can be long and straight like spaghetti
or the chains can be “cross linked”. This means that the chains hook up with other chains from the side
forming a web-like structure.
Common Polymers
Name
Basic Unit (monomer) Polymer
Use
H
CH
H CH3H CH3H CH3
3
Polypropylene
Clothing,
carpets
C
C
C C C C C C
H
H
Polydichloroethylene
(Saran)
Polytetrafluoroethylene
(Teflon)
Polyvinyl chloride
PVC
H
Cl
C
C
H
Cl
F
F
C
C
H
H
H H
Cl H
H H
Cl H
H
Cl
C
C
C
C
C
C
H
Cl H
F
F
F
F
Cl H
F
F
C
C
C
C
C
C
F
F
F
F
F
Sandwich wrap
Cl
Non-stick
coatings
F
F
H
Cl
H
Cl
H
Cl
H
Cl
H
C
C
C
C
C
C
H
H
H
H
H
H
C
F
C
H
Polystyrene
H
C
HC
HC
C
H2C
CH
H
C
CH
HC
CH
CH
HC
H
H
C
H
H
C
C
C
C
C
C
C
C
H
CH
H
HC
C
H
CH
H
CH
HC
HC
HC
C
H
CH
Hoses, pipes,
garbage bags
Coffee cups,
insulation,
Styrofoam
CH
C
H
Other common polymers include polyester (an ester) , rubber (a natural hydrocarbon) , chewing gum (a type
of rubber), nylon (an amide).
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Physical Properties
Boiling point:
Size:
In the same functional group the boiling point increases with increasing molar mass or chain length.
methane
pentane
hexane
hexadecane
CH4 -161ºC
C5H12 +36ºC
C6H14 +69ºC
C16H36 +287ºC
Branching:
If two compounds have the same molar mass the one with the least branching will generally have the
higher boiling point.
2,5-dimethylhexane
2,2,4octane
2-methylheptane
Trimethylpentane
CH3CH2CH2CH2CH2`CH2CH2CH3
C8H18
+125 ºC
CH3CHCH2CH2CH2CH2CH3
CH3
C8H18
CH3CHCH2CH2CHCH3
CH3
+119 ºC
C8H18
CH3
+108 ºC
CH3
CH3CCH2CHCH3
CH3
C8H18
CH3
+99 ºC
Functional Group:
The more functional groups that are present the higher the boiling point.
1-propanol
1,3-propandiol
1,2,3-propantriol
CH3CH2CH2OH
+ 97 ºC
CH2OHCH2CH2OH
+210 ºC
CH2OHCOHCH2OH
+290 ºC
The more polar a compound is the higher the boiling point: Use the following trends.
Nonpolar
Polar
H- bond
Polar and H-bonds
alcohols
carboxylic acids
Ethers
Alkanes
amines
amides
aldehydes
Alkenes
ketones
Alkynes
esters
Aromatics
Lowest boiling
Highest boiling
Propane –42ºC
Propanone / Propanal +46ºC
1-propanol +96ºC
Propanoic acid +141ºC
Methyl ethanoate +56ºC
Propanamide +213ºC
Solubilty:
Size:
In the same functional group the solubility increases with decreasing molar mass or chain length.
Functional Group:
The more functional groups that are present the higher the solubility.
The more polar a compound is the higher the solubilty: Use the following trends.
Nonpolar
Polar
Can H- bond
Polar and H-bonds
alcohols
carboxylic acids
Ethers
Alkanes
amines
amides
aldehydes
Alkenes
ketones
Alkynes
esters
Aromatics
Least soluble
Most soluble
~0 C’s / group
~3 C’s / group
~5 C’s / group
~6 C’s / group
Pentane
trace
3-pentanone 0.7 g/100mL 1-pentanol 2.7 g/100mL pentanoic acid 5.7 g/100mL
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