nomenclature

1
HYDROCARBONSNOMENCLATURE
2
LINEAR HYDROCARBONS
ALKANES
3
LINEAR HYDROCARBONS
4
THE PROBLEM
A problem arises when you have to name compounds
that all have the same formula.
If they are all C7 compounds, you cant call
them all heptane.
And there are millions of organic compounds ..
how can you get a unique name for each compound ?
5
THE 9 CONSTITUTIONAL ISOMERS OF HEPTANE
EACH ONE NEEDS A UNIQUE NAME. HOW IS IT DONE ?
6
IUPAC NOMENCLATURE
7
IUPAC RULES
systematic nomenclature
I nternational U nion of P ure and A pplied C
hemistry
colloquially
eye-you-pac
8
FEATURES OF THE IUPAC SYSTEM
It is a system where every compound (even
isomers) has a unique name.
If the rules are followed, everyone gets the same
name for a given compound.
Once given the name, anyone can draw the
structure of the compound.
WORKS BOTH DIRECTIONS
IUPAC
STRUCTURE
NAME
9
IUPAC METHOD
1. Find the longest continuous chain of
carbon atoms and name it (use linear names).
2. Number the chain starting from the end
nearest a branch.
3. Give each substituent a name based on the
number of carbon atoms it has. replace the
-ane ending with -yl
4. Give each substituent a locant number
determined by its location on the chain.
5. Assemble the name.
10
FINDING THE LONGEST CONTINUOUS CHAIN OF CARBON
ATOMS IS NOT ALWAYS SIMPLE
all possibilites must be examined
C-C
C-C-C-C-C-C-C-C-C
it wont always be the horizontal one as shown
here
C
9
try these also ..
C-C
C-C
C-C-C-C-C-C
C-C-C-
C-C-C
-C-C-C-C-C
C-
C
6
8
C
11
THE MAIN CHAIN AND ITS SUBSTITUENTS
substituent
main chain
C-C
C-C-C-C-C-C-C-C-C
C
substituent
Groups attached to the main chain are
called substituents.
12
NAMING SUBSTITUENTS
methyl ethyl propyl butyl pentyl hexyl heptyl octy
l nonyl decyl
hydrocarbon
stem ane
methane

change ending to -yl
substituent
stem yl
methyl

The stem indicates the number of carbons
13
ASSEMBLING A NAME
14
GENERAL STRUCTURE OF AN IUPAC NAME
number
word
word
suffix
MAIN CHAIN STEM
LOCANT
SUBSTITUENT
ENDING
name of the substituent
indicates the type of compound
indicates the number of carbon atoms in the chain
indicates position of the substituent on the chain
15
PUNCTUATION RULES
1. Numbers are separated from words by
hyphens
2-methyl.
2. Numbers are separated from numbers by
commas.
2,3- ..
example coming shortly
3. All words are joined - no breaks
methylhexane
16
HYDROCARBON EXAMPLES
17
ORGANIC NOMENCLATURE
4 3 2 1
butane
methyl
- find longest chain
- number from end nearest a branch
2-methylbutane
18
Find the Longest Continuous Carbon Chain
3-methylpentane
19
You Must Choose the LongestContinuous Carbon
Chain
4-ethylheptane
20
Number from the End Nearestthe First Substituent
7 6 5 4 3
2 1
4-ethyl-3-methylheptane
21
Number from the End Nearest theFirst Substituent
8 7 6 5 4 3
2 1
3-ethyl-5-methyloctane
22
Use di- With Two Substituents
1 2 3 4
2,3-dimethylbutane
23
MULTIPLIERS
DI- TRI- TETRA- PENTA- HEXA- HEPTA- OCTA- NONA- DE
CA-
These are ignored when alphabetizing
24
Every Substituent Must Get a Number
1 2 3 4 5 6
3,3-dimethylhexane
25
NAMES OF SOME COMMON ALKYL GROUPS
C1
methylene
methyl
CH3
CH2
C2
ethyl
CH2CH3
C3
propyl
CH2CH2CH3
CH-CH3
isopropyl
CH3
26
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27
Number from the End NearestFirst Substituent
10 9 8 7 6 5
4 3 2 1
2,7,8-trimethyldecane
28
Number from the End Which Hasthe First
Difference
1 2 3 4 5 6
7 8 9 10
3,4,8-trimethyldecane
29
A More-Highly-SubstitutedCarbon Takes Precedence
5 4 3 2 1
2,2,4-trimethylpentane
30
Number from the End Nearestthe First Difference
1 2 3 4 5
6 7 8
6-ethyl-3,4-dimethyloctane
31
Which end do we number from?
1 2 3 4 5 6
7 8
8 7 6 5 4 3
2 1
3-ethyl-6-methyloctane
32
1
octane
2
4
2,5-dimethyloctane
3
2,2-dimethyl-3-hexene
1,3-diethylcyclopentane
33
9
10
3-methylhexane
4-ethyl-2,3-dimethylheptane
11
5-ethyl-2,4,6-trimethyloctane
34
16
2,7,8-trimethyldecane
17
19
2-hexene
18
3,3-diethylpentane
4-ethyl-1,2-dimethylcycloheptane
35
SUMMARY
36
SOME THINGS TO REMEMBER
1 The base name always uses the longest chain
2 Number from the end nearest the first
substituent
3 Groups are placed in alphabetic order
a,b,c..
4 Multipliers are ignored in alphabetizing
diethyl e
5 Disubsubstituted carbons (two groups) are
more important than monosubstituted (one
group)
6 Numbers are separated from numbers by commas
2,3
7 Numbers are separated from words by hyphens
3-ethyl
8 The substituent and stem names are not
separate words methylhexane
9 Names are not capitalized unless they begin a
sentence
37
Block Diagram for Nomenclature
THE BASIC PATTERN
number of carbons in chain
name of substituent
location of substituent
may be repeated depending on number of
substituents
indicates location of functional group if ending
is different from -ane
designates functional group
38
CYCLIC COMPOUNDS
39
THE CYCLOALKANES
( cyclo ring )
cyclopropane
cyclopentane
cyclobutane
cyclohexane
40
CYCLOALKYL GROUPS
cyclopropyl
cyclobutyl
cyclopentyl
cyclohexyl
41
SOME CYCLOALKANES
1,3-dimethylcyclopentane
Drawn differently but same name.
1
2
1

2
3
3
4
3
1
2
2
1
3
3-ethyl-1,1-dimethylcyclobutane
1-ethyl-4-methylcyclohexane
The more substituted carbon takes precedence even
though E comes before M.
E before M
42
12
13
3,4-diethyl-2-hexene
cyclobutene
15
14
benzene
1,2-dimethyl-6-propylcyclodecane
43
20
3-ethyl-2-methylpentane
21
3-ethyl-1,5,5-trimethylcyclohexene
44
ALKENES AND ALKYNES
.. the suffix is the thing
.. it indicates the type of compound
45
ALKENES ( -ENE )
- Change the ending (suffix) from -ane to
-ene - Assign a locant number.
C
H
C
H
C
H
C
H
C
H
C
H
2
2
3
3
2-hexene
C
H
C
H
2
3
C
H
C
H
C
H
C
H
C
H
3
3
C
H
3-ethyl-1-cyclohexene
3
( 3-ethylcyclohexene )
4-methyl-2-pentene
In numbering, the double bond takes precedence
over substituents.
46
5
4-nonene
8
6
cyclopropane
7
6-ethyl-2-octyne
3,3-dimethylcyclopentene
47
ALKYNES ( -YNE )
The functional group has precedence in numbering.
2-hexyne
functional group
The suffix has precedence over any substituents
4-methyl-2-pentyne
48
Organic Nomenclature

• Assigning number for unsaturated centre

but-1-ene (Not but-3-ene)
pent-2-yne (Not pent-3-yne)
49
Organic Nomenclature

• Assigning number for more than one unsaturated
  centre

hexadeca-1,3-diene
50
Organic Nomenclature

• For hydrocarbons with both double and triple
  bonds

pent-1-en-3-yne (Not pent-4-en-2-yne)
51
Organic Nomenclature

• For hydrocarbons with both double and triple
  bonds

hexa-1,3-dien-5-yne (Not hexa-3,5-dien-1-yne)
52
PRECEDENCE
In numbering, functional groups take
precedence over substituents.
Since functional groups are indicated by
changing the suffix, and substituents are
indicated by prefix, the following rule applies
ANYTHING NAMED IN THE SUFFIX HAS
NUMBERING PRECEDENCE OVER ANYTHING NAMED IN THE
PREFIX
There is also an order of precedence for
functional groups named in the suffix. We wont
worry about this right now except to say that
functional groups of higher precedence are named
last in the suffix.
53
PRECEDENCE
continued
For our current discussion alkynes have greater
precedence than alkenes
thus -ene comes before -yne in the names of
compounds that have both functional groups
1 2 3 4 5 6
7 8 9
CH3-CH2-C C-CH2-CHCH-CH2-CH3
6-nonen-3-yne
Generally more complicated functional
groups (those with more bonds, or those with a
higher state of oxidation) have a higher priority.
. more on this later
54
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55
DEGREE OF SUBSTITUTION
.. how do you designate specific carbon
atoms within a structure ?
56
DEGREE OF SUBSTITUTION
C
C
PRIMARY CARBON
SECONDARY CARBON
CONNECTED TO TWO OTHER CARBONS
CONNECTED TO ONEOTHER CARBON
QUATERNARY CARBON
TERTIARY CARBON
CONNECTED TO THREE OTHER CARBONS
CONNECTED TO FOUR OTHER CARBONS
57
EXAMPLE
A hydrocarbon containing carbon atoms
with differing degrees of substitution
PRIMARY
QUATERNARY
TERTIARY
SECONDARY
All of the methyl groups (CH3) are primary.
58
Degree of Substitution Group Names
59
COMMON ALKYL GROUPS
.. special names for specific alkyl groups
( combinations of carbon and hydrogen )
MEMORIZE THESE THROUGH C5 !
60
NAMES OF SOME COMMON ALKYL GROUPS
C1
methine
methylene
methyl
CH3
CH2
CH
C2
ethyl
CH2CH3
C2 - has no isomers
C3
propyl
CH2CH2CH3
CH-CH3
isopropyl
CH3
61
NAMES OF SOME COMMON ALKYL GROUPS
( continued )
C4
C5
pentyl
CH2CH2CH2CH2CH3
butyl
CH2CH2CH2CH3
isopentyl
CH2CH2-CH-CH3
CH2-CH-CH3
isobutyl
CH3
CH3
CH3
sec
-butyl
CH-CH2-CH3
neopentyl
CH2-C-CH3
CH3
CH3
CH3
sec
-pentyl (not much used)
tert
-butyl
C-CH3
(
t
-butyl)
CH3CHCH2CH2CH3
CH3
(2)
CH3CH2CHCH2CH3
(3)
62
COMPLEX SUBSTITUENT NAMES - IUPAC
63
Naming Complex Substituents
The base name is derived from the longest chain
starting outward from the point of attachment,
which becomes carbon number 1. Other carbons are
substituents.
common name isopropyl

• (1-methylethyl)

64
Naming Complex Substituents

• (1,3-dimethylbutyl)

65
Naming Complex Substituents

• (2-ethyl-1,1-dimethylbutyl)

66
SPECIAL GROUP NAMES ARE OFTEN CONVENIENT ON A
LONG CHAIN
and allowed by the IUPAC
CH3
CH3-CH-CH3
8 9 10 11
CH3-CH-CH2-CH2-CH-CH2-CH2-CH-CH2-CH2-CH3
1 2 3 4 5
6 7
CH2-CH3
8-ethyl-5-isopropyl-2-methylundecane
67
BUT CAN USUALLY BE AVOIDED ON A SHORTER CHAIN
incorrect
1 2 3 4 5
6 7 8 9
6-sec-butyl-3-isopropylnonane
1 2
correct
-CH3
CH3-CH
6
CH3-CH2-
CH-CH2-CH2-CH
-CH2-CH2-CH3
3 4 5
CH3-
CHCH2CH3
7 8 9
3-ethyl-2,7-dimethyl-6-propylnonane
68
MAXIMIZE THE NUMBER OF SUBSTITUENTS
WHEN MORE THAN ONE CHAIN OF THE SAME LENGTH IS
POSSIBLE
ALWAYS PICK THE CHAIN WITH THE MOST
SUBSTITUENTS
This will avoid using the special groups in favor
of simpler ones .
69
SOME OTHER COMMON GROUPS
All these groups are named as substituents (
prefixes at the start of the name )
or
or C
H
6
5
Phenyl
F
C
l
B
r
I
Bromo
Iodo
Fluoro
Chloro
fluor ine
fluor o
N
O
2
halogen substituents use -o instead of -yl -
as does the nitro group
Nitro
70
IUPAC AND COMMON NAMES OF ALKYL HALIDES
IUPAC
COMMON
propyl chloride
1-chloropropane
n -propyl chloride
2-bromo-2-methylpropane
t -butyl bromide
tert -butyl bromide
1-fluoro-2,2-dimethylpropane
neopentyl fluoride
1-iodocyclopentane
cyclopentyl iodide
71
IUPAC AND COMMON NAMES OF ALCOHOLS
IUPAC
COMMON
ethanol
ethyl alcohol
2-propanol
isopropyl alcohol
2-methylpropanol
isobutyl alcohol
2-butanol
sec -butyl alcohol
72
SOME FINAL EXAMPLES
73
If you can name this,you can name anything!

• 1 2 3 4 5
  6
  7
  8 9
• 4-isopropyl-2,6,6-trimethylnonane

74
This Should Be Fun
1 2 3
1 2 3 4 5
6 7 8 9
5-(1-ethyl-1-methylpropyl)-5-propylnonane
75
Functional Groups

• Term used to refer to parts of organic molecules
  where reactions tend to occur.

76
Alcohols

• Contain one or more hydroxyl groups, OH

• Named from parent hydrocarbon suffix changed to
  -ol and number designates carbon to which
  hydroxyl is attached.

77
Ethers

• Tend to be quite unreactive.
• Therefore, they are good polar solvents.

78
Carbonyl Compounds

• Contain CO double bond.
• Include many classes of compounds.

79
Aldehydes

• At least one hydrogen attached to carbonyl
  carbon.

80
Ketones

• Two carbons bonded to carbonyl carbon.

81
Carboxylic Acids

• Have hydroxyl group bonded to carbonyl group.
• Tart tasting.
• Carboxylic acids are weak acids.
• Naming
• _____oic acid

CH3COOH
82
Carboxylic Acids
83
Esters

• Products of reaction between carboxylic acids and
  alcohols.
• Found in many fruits and perfumes.

butanoate
84
Amines

• Organic bases.
• Generally have strong, unpleasant odors.

85
Amides

• Formed by reaction of carboxylic acids with
  amines.
• This is the reaction that occurs between amino
  acids

86
Amino Acids and Proteins

• A condensation reaction between the amine end of
  one amino acid and the acid end of another
  produces a peptide bond.

87
PHYSICAL PROPERTIES
OF HYDROCARBONS
88
REACTIONS OF HYDROCARBONS
89
HYDROCARBON REACTIONS
Alkanes and cycloalkanes are quite unreactive
toward most reagents.
C
H
C
H
C
H
C
H
3
2
3
C
H
3
C
H
C
H
C
H
C
H
C
H
3
2
2
2
3
They have no functional group.
90
THE ECONOMICALLY IMPORTANT REACTION IS
OXIDATION
91
OXIDATION (COMBUSTION)
All hydrocarbons burn to form carbon dioxide,
water and heat. The heat can be used to heat
homes or run engines.
CnH2n2 O2 n CO2 (2n2)/2
H2O Heat
92
EXAMPLES OF OXIDATION (COMBUSTION)
CH4
methane
natural gas
example
CH4 2 O2 CO2 2 H2O Heat
Each carbon gives a CO2 molecule, and every two
hydrogens give a water molecule.
NOTE
example
C3H8 propane
liquefied propane
CH3CH2CH3 5 O2 3 CO2 4 H2O
Heat
93
SOURCES OF HYDROCARBONS
94
NATURAL SOURCES OF HYDROCARBONS
90-95 methane (C1-C4) 5-10
ethane small amounts of propane, butane and
2-methylpropane
NATURAL GAS
Thick viscous mixture of hundreds of hydrocarbons
(mostly C5-C20).
PETROLEUM
Formed from the decomposition of ancient marine
plants and animals.
Mixture of carbon and solid, high molecular
weight hydrocarbons (gtC20).
COAL
COAL TAR
Many aromatic and heteroaromatic compounds.
95
CRUDE PETROLEUM IS DISTILLED AT A REFINERY
Gasoline, diesel fuel, and aviation fuel are
mixtures of hydrocarbons.
Read the essay on pp 204-207
Distillation of Crude Petroleum
Gases Naphtha Kerosene Fuel Oil Lubricating
Oil Asphalt
below 20o 20 - 200o 175 - 275o 250 -
400o above 350o residues
C3-C4 C5-C12 C9-C15 C15-C18
LPG Gasoline Diesel Fuel
96
Read the essay on pp 221-223
GASOLINE
Complex mixture of C5 to C12 hydrocarbons
Aromatic hydrocarbons are best, and branched
better than linear hydrocarbons.
toluene
octane rating 120
heptane
2,2,4-trimethylpentane
(isooctane)
benzene
octane rating 0
octane rating 100
octane rating 106
the standard - against which others are compared
97
HALOGENATION
Halogenation replaces one or more hydrogens in a
molecule with a halogen most commonly a
chlorine.
It converts a relatively inert hydrocarbon
molecule to one that has a reactive functional
group a site where chemical reactions can take
place.
98
Halogenation of Alkanes
chlorination
free-radical substitution reaction
examples
CH4 Cl2 CH3Cl HCl
CH3CH2CH3 Cl2 CH3CHCH3 HCl
Cl
takes place at a refinery or a chemical plant -
not easy to do in the lab
CH3CH2CH2-Cl
99
THE REACTION MUST BE INITIATED
It does not occur in the dark.
Exposure to ultraviolet light (sunlight) will
start the reaction.
An electric spark or heat will also start the
reaction.
Once reaction starts, it is exothermic and
continues almost explosively.
The first step is thought to be the dissociation
of chlorine
..
..
..
.
Cl-Cl
hn



2
Cl
chlorine atoms
..
..
..
or D
(radicals)
diatomic molecule
100
ABSTRACTION OF HYDROGEN
BY A CHLORINE FREE RADICAL (ATOM)
unpaired electron free radical
..
.
.
.
C H

Cl
HYDROGEN ABSTRACTION

..
Chlorine takes the hydrogen and one of its
electrons
101
MECHANISM OF CHLORINATION OF METHANE
CHAIN REACTION
dissociation
REPEAT ING S TEPS
hydrogen abstraction
cycle repeats
chlorine scission
102
4. Termination Steps
recombinations
These steps stop the chain
Termination could be a combination of these steps
or it could be determined by which species are
still present at the end of the reaction.
103
THE PREVIOUS EXAMPLES GIVEN ASSUMED
MONOCHLORINATION
( one chlorine added )
BUT the reaction can repeat itself
COMMON NAMES
104
YOU CAN LIMIT THE REACTION TO MONOCHLORINATED
PRODUCTS IF YOU RESTRICT THE AMOUNT OF Cl2
How many different monochlorination products can
be formed ?
Which product will form in greatest amount?
do on board
105
LOOK FIRST AT A SIMPLER CASE
MONOCHLORINATION OF PROPANE
CH3CH2CH3 Cl2 CH3CHCH3
CH3CH2CH2-Cl
Cl
limited amount
A
B
QUESTION
WHAT ARE THE RELATIVE AMOUNTS OF A AND B ?
IS IT STATISTICAL ( 1 3 ) (2 6 ) ?
DOES SOMETHING ELSE CONTROL THE OUTCOME ?
106
MONOCHLORINATION OF PROPANE
STATISTICAL VERSUS EXPERIMENTAL RESULTS
CH3CH2CH2-Cl
A
B
STATISTICAL PREDICTION 25 75
CH3-CH2-CH3 3 1
107
EXPERIMENTAL RESULTS SHOW
Tertiary hydrogens react faster than secondary
hydrogens and secondary hydrogens react faster
than primary hydrogens.
SELECTIVITY TERTIARY gt SECONDARY gt
PRIMARY
Hydrogens are classified according to the type
of carbon they are attached to Primary
Hydrogens are those attached to primary
carbons Secondary Hydrogens are those attached
to secondary carbons Tertiary Hydrogens
are those attached to tertiary carbons
CH3CHCH3
CH3CH2CH3
H
Primary Hydrogens (in red)
Secondary Hydrogens (in red)
more reactive than primary hydrogens
108
RETURN TO THE PREVIOUS QUESTION .
Which monochloro isomer will form in greatest
amount?
tertiary hydrogen
major product
however other products will also form
109
NOTICE THE APPLICATION OF THE GROUP DESIGNATIONS
Now you can begin to see the usefulness of the
terms
primary
methyl
methylene
secondary
methine
tertiary
quaternary
They not only designate different parts of
the molecule, but they also define different
degrees of reactivity.
110
REGIOSELECTIVE
and
REGIOSPECIFIC
111
CHLORINATION IS A REGIOSELECTIVE REACTION
REGIOSELECTIVE REACTION
One of the products is favored (formed
in larger amount than the others) but it is not
the only product formed.
You get a mixture of major and minor products.
regio refers to a region of the molecule
selective reacts mostly at one place
112
CHLORINATION IS NOT REGIOSPECIFIC
REGIOSPECIFIC REACTION
A Single product (100) is formed when two
or more products are possible.
The product formed is the only product.
regio refers to a region of the molecule
specific reacts at only one place (100)
113
CONFORMATIONS
114
FREE ROTATION
MOST ATOMS ATTACHED BY A SINGLE BOND ARE FREE TO
ROTATE AROUND THE BOND
THAT IS - THE TWO ENDS OF THE BOND CAN ROTATE
RELATIVE TO EACH OTHER
THE CARBON AND THREE HYDROGEN ATOMS ON THE RIGHT
END OF THE BOND CAN SPIN RELATIVE TO THE CARBON
AND OTHER THREE HYDROGENS ON THE LEFT END OF THE
BOND
fix
rotate
115
CONFORMATIONS
Different internal arrangements of the atoms in a
molecule that differ by rotation(s) about one or
more of the single bonds.
CONFORMATIONS ARE NOT ISOMERS
Conformations are different arrangements of the
SAME MOLECULE
The connection pattern of the atoms does not
change.
116
CONFORMATIONS OF ETHANE
A SIMPLE EXAMPLE
117
CONFORMATIONS OF ETHANE
(EXTREMES)
ECLIPSED
STAGGERED
SAWHORSE PROJECTIONS
118
CONFORMATIONS OF ETHANE
SAWHORSE DIAGRAMS
eclipsed
staggered
119
TWO CONFORMATIONS OF ETHANE
NEWMAN PROJECTIONS
ECLIPSED
STAGGERED
H
H
H
H
H
Looking down the carbon-carbon bond.
H
H
H
H
H
H
H
NEWMAN PROJECTIONS
120
CONFORMATIONS DIFFER IN ENERGY
numerous other conformations in between
EXTREMES
12.1 kJ/mol
eclipsed
3 Kcal/mol
ENERGY
staggered
0 kJ/mol
0 Kcal/mol
The staggered conformation has a lower energy.
121
THERE IS A LARGER NUMBER OF DIFFERENT
CONFORMATIONS WITH BUTANE
For the butane molecule, unlike ethane or
propane, not all of the staggered and eclipsed
conformations are identical when looking down
the C2-C3 bond.
Each of these unique conformations has a
special name that you must learn.
These are enumerated in Reading SIX in this
weeks work Or consult CH102.
122
Isomers and polymers
123
Structural Isomers

• Pentane and 2-methylbutane are both C5H12.

1-butene
2-butene

2-methylpropene
cyclobutane
methylcyclopropane

• C4H10 has 2 isomers (2-methylpropane, butane).
  C4H8 has more isomers because the position of the
  double affects the name and because ring
  structures can be drawn.

124
Geometric Isomers

• cis same side, trans opposite sides
• 1,2-dichloroethene requires cis or trans.
• 1,2-dichloroethane does not require cis or trans
  because they would both represent the same
  molecule (to move chlorine from the same side to
  opposite sides only requires that the C C
  single bond be rotated).

cis-1,2-dimethylcyclopentane
trans-1,2-dimethylcyclopentane
125

• 1,1-dimethylcyclopentane
• A molecule is relatively inflexible when a
  multiple (double or triple) bond is present or if
  a ring structure (including benzene) exists.
• a) not isomers (they dont have the same chemical
  formula C5H12 vs. C5H10)
• b) structural isomers (same as question 1)
• c) geometric isomers
• d) not isomers (both diagrams represent the
  exact same molecule)

126
Polymers

• Monomer the smallest repeating unit of a polymer
  (propene in polypropylene).
• Polymer a long chain molecule made up of many
  small identical units (monomers).
• Addition polymerization a reaction in which
  unsaturated monomers combine with each other to
  form a polymer.
• Teflon, polypropylene, polyester, polyethylene
  (pop bottles, grocery bags), polystyrene (packing
  material), Plexiglas, polyvinyl chloride (vinyl),
  natural rubber, etc.

127
Geometric Isomers
cis-1,2-dichlorocyclopentane
trans-1,2-dichlorocyclopentane
cis-1,2-dichloroethene trans-1,2-dichloroethene
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