uses and cracking of crude oil

Question 1

What are the crude oil various uses in modern life

Answer 1

Oil provides the fuel for modern transport = cars, trains , planes , kerosene ,diesel, heavy fuel oil and LPG all comes from crude oil

The petrochemical industry uses some of the hydrocarbons from crude oil as a feedstock to make new compounds for use in things like polymers, solvents , lubricants and detergents.

All the products you get from crude oil are examples of organic compounds. The reason you get such large variety of products is because carbon atoms can bond together to form homologous series = contains similar compounds with many properties in common. Alkanes and Alkenes are both examples of homologous series.

Question 2

Why is cracking used ?

Answer 2

Short - chain hydrocarbons are flammable so make good fuels and are in high demand. However, long - chain hydrocarbons form thick gloopy liquids like tar which aren’t all that useful so

a lot of longer alkane molecules produced from fractional distillation are turned into smaller, more useful ones by a process called cracking

Question 3

Useful products of cracking

Answer 3

• fuel, alkane

Question 4

What’s another type of hydrocarbon cracking produces?

Answer 4

Alkene = more reactive than alkane
There used as a starting material when making lots of other compounds and can be used to make polymers

Question 5

Method to test for alkene

Answer 5

Bromine water
1) When orange bromine water is added to an alkane -> no reaction , remain bright orange
2) if added to an alkene -> Bromine reacts with the alkene to make a colourless compound + Bromine water is discoloured

Question 6

Different methods of cracking

Answer 6

1) Cracking is a thermal decomposition reaction - breaking molecules down by heating
2) Heat long-chain hydrocarbon to vaporise them
3) then vapour passed over a hot powdered aluminium oxide catalyst

4) The long - chain molecules split apart on the surface of the specks of catalyst (catalytic cracking)
5) You can also crack hydrocarbons if you vaporise them , mix them with steam and heat them to a high temperature ( Steam cracking)

Question 7

Do question on page 152

Answer 7

AQA