•Atom or group of atoms that
replaces a hydrogen atom in a
hydrocarbon.
•Functional groups give the
molecule personality.
Functional Group
•Each functional group gives the
molecule distinctive chemical &
physical properties.
•Molecules with functional groups
contain at least one atom that is not
C or H. Not hydrocarbons!
Functional Group
•Derived from the name of
the hydrocarbon with the
same number of carbon atoms.
Names of molecules with
functional group
•One or more H in an alkane is
replaced with a halogen (F, Cl,
Br, or I).
•General formula = R-X.
–X is the halogen.
–R is the alkyl branch.
Halides or halocarbons or
alkyl halides
•Likely to be polar molecules,
unless very symmetric.
•Dipole-dipole interactions.
Properties of Halides
•Have POLES.
•The electron cloud is lop-sided. One
end of molecule is electron-rich & the
other electron-poor.
•Dipole-dipole interactions.
Polar Molecules
•Atoms in molecule have very
different electronegativities.
•Molecule is not symmetrically
shaped.
Polar Molecules
•Higher mp, bp, Hf, Hv than
the corresponding alkanes.
•Lower rate of evaporation &
vapor pressure than the
corresponding alkanes.
Properties of Halides
•One or more hydrogens in a
hydrocarbon replaced with an OH
group.
•General formula = R-OH.
•The OH or hydroxyl group does
NOT ionize in water.
Alcohols
•NONelectrolytes. No H+ or
OH- ions in solution.
•Do NOT turn litmus red, etc.
Properties of Alcohols
•Contain O-H bond. Molecules
tend to be polar. Dissolve in
water.
•Hydrogen bonding takes place
between alcohol molecules.
Higher mp, bp than corresponding
alkanes.
Properties of Alcohols
•Replace final –e of corresponding
alkane name with –ol.
Naming Alcohols
•Monohydroxy: 1 -OH group.
•Dihydroxy: 2 –OH groups.
•Trihydroxy: 3 -OH groups.
Classification of alcohols by
number of -OH groups.
•Primary: OH group at end
carbon.
•Secondary: OH group on
middle carbon.
•Tertiary: OH group at
branch-point carbon.
Further classification of monohydroxy
alcohols by carbon to which OH group
attached.
•Contain an O atom bridge connecting 2
alkyl branches.
•General Formula: ROR‘
•R & R‘ are alkyl groups (the 2 branches).
•R & R‘ can be same or different.
Ethers
Tend to be nonpolar.
Properties of Ethers
1. Name branches
alphabetically.
2. Stick the word “ether” at
the end.
Naming Ethers
C in a chain that has a double
bond to an O.
>C=O

O
or C
Carbonyl Group
Contain a carbonyl group at
the end of the chain.
Aldehydes
Replace final “e” of
corresponding alkane name
with “al.”
Naming Aldehydes
Contain a carbonyl group on a
carbon atom inside the chain,
not at the end.
Ketones
Replace final “e” of
corresponding alkane name
with “one.”
Naming Ketones
Carbonyl group is quite polar.
Tend to be soluble in both
polar & nonpolar solvents.
Properties of ketones
Contain a –COOH group at the
end of the molecule.

O
-C-O-H
Organic Acids
The H in the –COOH group is
acidic!

O
-C-O-H
Organic Acids
Turn litmus red.
Electrolytes!

O
-C-O-H
Properties of organic acids
Replace the final –e of the
corresponding alkane name
with “-oic acid”
Naming organic acids
Contain 2 oxygens!
1) Bridge O in the middle of
the chain.
2) Carbonyl O right next door.
Esters
R-CO-OR‘
Bridge O
Carbonyl O

O
R-C-O-R'
General formula of esters
1. Name alkyl branch next to
bridge O.
2. Name branch with carbonyl
group.
3. Replace –e of corresponding
alkane name with -oate.
Naming Esters
Format of esterification rxn:
Alcohol + Org. Acid  Ester + H2O
Formation of Esters
HO
 

 
 
 
H H H
HCCOCCCH + H2O
H
H H H




H O






HHH
HCCOH + HOCCCH
HHH
H
Formation of Esters
1. Replace H in an alkane with –
NH2 group.
2. Replace final –e in alkane name
with amine.
3. # gives location of NH2 group.
4. Analogous to alcohols
Amines
1. Tend to smell really bad.
2. Contain N-H bond. Exhibit Hbonding between molecules.
Properties of Amines

1. Contain NH2 group bonded to a
carbonyl group.
O
2. General formula: R-C-NH2
Amides
1. Find name of corresponding
alkane.
2. Drop final -e & add –amide.
3. Never need a # - Always at
the end.
Naming Amides
1. Contain COOH group at end.
2. C right next door has NH2 or
amino group.
Amino Acids
1. Large molecules made of
chains of smaller units
covalently bonded together.
Polymer
1. Each individual unit of a
polymer
Monomer
1. Reaction leading to formation
of polymers
Polymerization