-OH functional group (hydroxyl group)

Hydroxyl group: physical/ chemical properties of alcohols

CH3OH (methanol):
high performance fuel (efficient combustion)
Chemical feedstock- starting material in industrial syntheses
Adhesive
Solvent

C2H5OH (ethanol):
alcoholic drinks
Fuel
Solvent
Feedstock

Suffix: -ol
Position of OH functional group
e.g. 2-methylbutan-2,3-diol

Volatility and boiling points: Alcohols have lower volatility than alkanes because:
Liquid: hydrogen bonds hold alcohol molecules together
(must be broken change into gas) more energy required overcome hydrogen bonds than london forces

Water solubility:
Alcohols more water soluble than alkanes because: alkanes are non-polar cannot form hydrogen bonds in H2O
Methanol/ ethanol: soluble in water- hydrogen bonds form between polar O-H group alcohol and H20 molecules
Solubility decreases = carbon atoms increase (influence OH group decreases)

Alkanes: non-polar bonds because electronegativity of hydrogen and carbon are very similar = NON-POLAR (intermolecular forces: LONDON FORCES)

Alcohols: polar O-H bond because difference electronegativity oxygen and hydrogen atoms = POLAR (intermolecular forces: london forces and HYDROGEN BONDS between polar O-H groups

Primary/ Secondary/ Tertiary: number hydrogen atoms and alkyl groups attached carbon atom that contains OH functional group

Primary alcohols:
E.g. methanol/ ethanol
-OH group attached carbon atom attached 2 hydrogen atoms/ 1 alkyl group

Secondary alcohols:
E.g. propan-2-ol/ pentan-3-ol
-OH group attached carbon atom attached 1 hydrogen atom/ 2 alkyl groups

Tertiary alcohols:
E.g. 2-methylpropan-2-ol/ 2-methylbutan-2-ol
-OH group attached carbon atom attached NO hydrogen atoms/ 3 alkyl groups