Functional Group

•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!

Names of molecules with functional group

•Derived from the name of the hydrocarbon with the same number of carbon atoms.

Halides or halocarbons or alkyl halides

•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.

Properties of Halides

•Likely to be polar molecules, unless very symmetric.

•Dipole-dipole interactions.

Polar Molecules

•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.

Properties of Halides

•HigherHigher mp, bp, Hf, Hv than the corresponding alkanes.•LowerLower rate of evaporation & vapor pressure than the corresponding alkanes.

Alcohols

•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.

Properties of 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.

Naming Alcohols

•Replace final –e of corresponding alkane name with –ol.

Classification of alcohols by number of -OH groups.

•Monohydroxy:Monohydroxy: 1 -OH group.•Dihydroxy:Dihydroxy: 2 –OH groups.•Trihydroxy:Trihydroxy: 3 -OH groups.

Further classification of monohydroxy alcohols by carbon to

which OH group attached.

•Primary:Primary: OH group at end carbon.•Secondary:Secondary: OH group on middle carbon.•Tertiary:Tertiary: OH group at branch-point carbon.

Ethers

•Contain an O atom bridge connecting 2 alkyl branches.

•General Formula: ROR‘

•R & R‘ are alkyl groups (the 2 branches).

•R & R‘ can be same or different.

Properties of Ethers

Tend to be nonpolar.

Naming Ethers

1. Name branches alphabetically.

2. Stick the word “ether” at the end.

Carbonyl Group

C in a chain that has a double bond to an O.

>C=O or C

O

Aldehydes

Contain a carbonyl group at the end of the chain.

Naming Aldehydes

Replace final “e” of corresponding alkane name

with “al.”

Ketones

Contain a carbonyl group on a carbon atom inside the

chain, not at the end.

Naming Ketones

Replace final “e” of corresponding alkane name

with “one.”

Properties of ketones

Carbonyl group is quite polar. Tend to be soluble in

both polar & nonpolar solvents.

Organic Acids

Contain a –COOH group at the end of the molecule.

-C-O-H

O

Organic Acids

The H in the –COOH group is acidic!

-C-O-HH

O

Properties of organic acids

Turn litmus red.Electrolytes!

-C-O-HH

O

Naming organic acids

Replace the final –e of the corresponding alkane name

with “-oic acid”

Esters

Contain 22 oxygens!1) Bridge O in the middle of

the chain.2) Carbonyl O right next

door.

General formula of esters

R-COO-OOR‘

R-C-OO-R'

Carbonyl OCarbonyl O Bridge OBridge O

OO

Naming Esters

1. Name alkyl branch next to bridge O.

2. Name branch with carbonyl group.

3. Replace –e of corresponding alkane name with -oate.

Formation of Esters

Format of esterification rxn:

Alcohol + Org. Acid Ester + H2O

Formation of Esters

HCCOH + HOCCCH

H

H

O

H

H H H

H H

HCCOCCCH + H2O

O

H

H

H H H

H H H

Amines

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

Properties of Amines

1. Tend to smell really bad.

2. Contain N-H bond. Exhibit H-bonding between molecules.

Amides

1. Contain NH2 group bonded to a carbonyl group.

2. General formula: R-C-NH2

O

Naming Amides

1. Find name of corresponding alkane.

2. Drop final -e & add –amide. 3. Never need a # - Always at

the end.

Amino Acids

1. Contain COOH group at end.2. C right next door has NH2 or

amino group.

Polymer

1. Large molecules made of chains of smaller units covalently bonded together.

Monomer

1. Each individual unit of a polymer

Polymerization

1. Reaction leading to formation of polymers