Transcript Petrochemicals - MullisChemistry

Hydrocarbons
Unsaturated hydrocarbons
– Double and triple bonds between carbons
– Not every carbon has each of its 4 electrons
bonded to 4 different atoms
– More chemically reactive than saturated
compounds, or alkanes
– Unsaturated hydrocarbons include alkenes
(double bonds) and alkynes (triple bonds)
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Parent hydrocarbon prefixes
# Carbon
atoms
Example
1
2
3
4
5
6
7
8
9
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CH4
methane
C2H6
ethane
C3H8
propane
C4H10
butane
C5H12
methethpropbutpenthexheptoctnondec-
As attached groups:
Functional Group
group
name
pentane
-CH3
-C2H5
-C3H7
-C4H9
methyl
ethyl
propyl
butyl
C6H14
hexane
-C5H11
pentyl
C7H16
heptane
C8H18
octane
C9H20
nonane
C10H22
decane
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4.
5.
Naming Organic Compounds
Name the parent hydrocarbon: Use the
LONGEST STRAIGHT chain of carbon atoms.
Add the name of the alkyl groups attached to the
chain. If more than one group is attached, use the
proper numerical prefix to indicate how many
groups are attached. (2=di, 3-tri,etc.)
Assign numbers to the carbons in the parent
chain. Assign so that attached groups are at the
lowest number possible.
Insert the numbers in front of the proper group.
Separate position numbers from names with
hyphens.
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Example: Naming Organic Compounds
1. Name the parent hydrocarbon.
CH3 – CH – CH2 – CH – CH – CH3
hexane
CH3
CH3 CH3
2. Add the name of the alkyl groups attached to the chain.
3 methyl groups: trimethylhexane
3. Assign numbers to the carbons in the parent chain.
6
5
4
3
2
1
CH3 – CH – CH2 – CH – CH – CH3
CH3
CH3 CH3
4-5. Insert position numbers and add hyphens.
2,3,5-trimethylhexane
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Name the following compounds
1. CH3 – CH – CH2 – CH2 – CH3
CH3
2. CH3 – CH – CH2 – CH2 – CH – CH3
|
|
CH3
CH3
3. CH3 – CH – CH2 – CH2 – CH3
CH2
CH2
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Unsaturated hydrocarbons
•
•
•
•
Single bond between carbons: -ane
Double bond between carbons: -ene
Triple bond between carbons: -yne
Examples:
H
H
H C C H
H H
ethane
C2H6
H
CnH2n+1
CnH2n
CnHn
H
C
C
H
H C C H
H
ethene
C2H4
ethyne
C2H2
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Other Functional Groups
Compound
Formula
Example
Alcohol
R-OH
hydroxyl group
1-propanol
Alkyl Halide
-X
X = any halide
1,2-dibromopropane
Ether
R-O-R’
one oxygen bonded to 2
hydrocarbon groups
diethyl ether
CH3-CH2 –O--CH2--CH3
Aldehyde
O
||
R-C-H
Carbonyl group attached
to end carbon
Ethanal
Ketone
O
||
R-C-R’
Carbonyl group attached
to a middle carbon
2-propanone O
||
CH3—C-- CH3
Carboxylic Acid
O
||
R-C-OH
Carboxyl group
Ester
O
||
R-C-O-R’
Carboxyl group without
the H
O
||
CH3—C--H
ethanoic acid O
||
CH3—C—OH
methyl ethanoate O
||
CH3—C—O-- CH3
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Cyclic Compounds
• Cycloalkanes
– Saturated carbons joined in a ring
– Example is cyclohexane, C6H12
– Add cyclo- to beginning of name if the alkane is known
to be arranged in a circle (CnH2n). No position number
is needed if only one alkyl group is attached.
• Aromatic compounds
– Unsaturated: Contains 3 double bonds
H-C
– Example is benzene, C6H6
C-H
H-C
CH3CH2-
C-H
-CH3
1-ethyl-4-methylbenzene
H-C
C-H
benzene
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Addition Reactions
• Water adds to ethene: The double bond is broken and
an H attaches to one carbon and the OH attaches to the
other carbon.
H
H
HH
C C + H-OH
H-C-C-H
H
H
HH
• Ethene can add to itself, breaking double bonds to
attach to one molecule after another.
• A monomer is a small unit; when additional
monomers are attached repeatedly, a long-chain
polymer is formed.
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Addition Polymers
• Polyethylene is a polymer made from the monomer
ethene. Zip-lock bags are usually made from lowdensity polyethylene.
• Common polymer variations replace one of ethene’s
hydrogens with another unit, such as a halogen atom
(F or Cl), Cyanide (CN), or benzene (C6H6).
– Vinyl chloride
– Acrylonitrile
– Styrene
polyvinyl chloride
polyacrylnitrile
polystyrene
• Atoms that compose the monomers determine the
properties of the polymer.
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