1. 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)

2. Parent hydrocarbon prefixes
# Carbon atoms
Example
1 meth-
CH4 methane
2 eth-
C2H6 ethane
3 prop-
C3H8 propane
4 but-
C4H butane
5 pent-
C5H pentane
6 hex-
C6H hexane
7 hept-
C7H heptane
8 oct-
C8H octane
9 non-
C9H nonane
10 dec-
C10H22 decane
As attached groups:
Functional group
Group name
-CH3
methyl
-C2H5
ethyl
-C3H7
propyl
-C4H9
butyl
-C5H11
pentyl

3. 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.

4. Example: Naming Organic Compounds
Name the parent hydrocarbon.
CH3 – CH – CH2 – CH – CH – CH3 hexane
CH3 CH3 CH3
Add the name of the alkyl groups attached to the chain.
3 methyl groups: trimethylhexane
Assign numbers to the carbons in the parent chain.
CH3 – CH – CH2 – CH – CH – CH3
4-5. Insert position numbers and add hyphens.
2,3,5-trimethylhexane

5. Name the following compounds
1. CH3 – CH – CH2 – CH2 – CH3
CH3
CH3 – CH – CH2 – CH2 – CH – CH | |
CH CH3
3. CH3 – CH – CH2 – CH2 – CH3
CH2
2-methyl pentane
#2: 2,5-dimethyl hexane
#3: 3-methyl hexane

6. Unsaturated hydrocarbons
Single bond between carbons: -ane CnH2n+1
Double bond between carbons: -ene CnH2n
Triple bond between carbons: -yne CnHn
Examples: C H
ethane
C2H6 C H
ethene
C2H4 C H
ethyne
C2H2

7. 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 O
CH3—C--H
Ketone
R-C-R’
Carbonyl group attached to a middle carbon
2-propanone O
CH3—C-- CH3
Carboxylic Acid
R-C-OH
Carboxyl group
ethanoic acid O
CH3—C—OH
Ester
R-C-O-R’
Carboxyl group without the H
methyl ethanoate O
CH3—C—O-- CH3

8. Cyclic Compounds Cycloalkanes Aromatic compounds
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
Example is benzene, C6H6
C-H
H-C
benzene
1-ethyl-4-methylbenzene
CH3CH2-
-CH3

9. 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 H H
C C H-OH H-C-C-H
H H H H
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.

10. Addition Polymers
Polyethylene is a polymer made from the monomer ethene. Zip-lock bags are usually made from low-density 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 polyvinyl chloride
Acrylonitrile polyacrylnitrile
Styrene polystyrene
Atoms that compose the monomers determine the properties of the polymer.