Organic CHEMISTRYAPPLICATIONSGr 12 Physical Science

Mrs KL FALING

APPLICATIONS1. Combustion 2.The

preparation of Esters

COMBUSTION

Alkanes are the most important fossil fuels

When reacting with oxygen they produce a lot of heat (EXOTHERMIC)

Excellent fuels

(Also called oxidation)

In conditions where oxygen levels are good Carbon dioxide is formed and in poor oxygen conditions carbon monoxide is formed.

Example: Hexane in sufficient oxygen:

Exercise

Methane + Sufficient oxygen (complete)

Ethane + Poor oxygen (incomplete)

Propane + Sufficient oxygen

Octane + Insufficient oxygen

Notes:

Methane gas released when plants rot

Methane and Ethane gas used as fuels

Propane and butane liquefy under pressure used widely in gas heaters and stoves

Butane used in cigarette lighters

Octane is a liquid and used as petrol in cars.

The preparation of esters

An ester is the product an acidic catalysed condensation reactionAcid is required to accelerate the reactionWater is a product formed

The process is known as ESTERIFICATION

ESTERIFICATION

Reaction of a carboxylic acid and an alcohol

Needs a catalyst and dehydrating agent (H2SO4) –concentrated

Heat is added

EXAMPLES

Practice

Propanol + Ethanoic acid

Ethanol + propanoic acid

Methanol + Butanoic acid

Butanol + Methanoic acid

HOMEWORK

Ex 8 page 102 number 1 - 11

ANSWERS