HideShow resource information


Hydrocarbon is a compound made from just hydrogen and carbon atoms

1 of 13

Naming compounds

1st part of name
No of carbon atoms first part of name
1. Meth
2. Eth
3. Prop
4. But
5. Pent
6. Hex
7. Hept
8. Oct
9. Non
10. Dec
2nd part depends on the family of chemicals
E.g. Alkanes all end in ane
Alkanes all end in ene
Alcohol all end in ol

2 of 13

Drawing molecules

Contain just single bond (saturated molecules)

To work out the number of hydrogens in an Alkane you double the number of carbons and add 2
For alkane - Cn H2n + 2

Contain a double bond (unsaturated molecules)

To get h double the amount of c
For Alkenes - CNH2n

3 of 13

Crude oil

Crude oil is a mixture if different hydrocarbons. They vary in size from 1 carbon atom to long to 100 carbon atoms long

4 of 13

Fractional distillation

This sorts out/separate the different sized oil fractions if molecules

5 of 13

Processing crude oil

At an oil refinery, crude oil from rocks under seabed is turned into useful products by separating it into different sized molecules called fractions.

6 of 13

A fractionating column

1. The crude oil is heated and turned into a vapour
2. The bottom of the fractionating column is hotter than the top
3. As the oil vapour rises up the column, it cools and turns back into a liquid
4. The small molecules turn back into liquids near the top of the column
5. The longer molecules change back into a liquid and exit near the bottom of the column
6. Fractional distillation works better because the different sized molecules have got different boiling points so they change back into a liquid at different points

7 of 13


Gases given off by burning fuels:
-water vapour (H2O)
-carbon dioxide if there isn't a good oxygen supply

-Carbon monoxide if there's not enough oxygen
-sometimes you get sulphur dioxide made if there is sulphur in the fuel
-also get soot =unburnt carbon
or smoke = smoke particles

8 of 13

Testing for Alkenes

-use bromine water that is orange/brown
-with an Alkene, the bromine water goes colourless
-with an alkane it stay ps orange/brown

9 of 13


Cracking is breaking the long hydrocarbon molecules into more useful short ones

Cracking needs:
-high temperature-to break the molecules
-catalyst-to speed up the reaction

10 of 13

Polymers (plastic)

Plastics are made by polymerisation. This is where small molecules called monomers join together to make long molecules called a polymer (plastic)

11 of 13

Smart polymers

Smart polymer - hydrogel
Properties - absorbs large volume of water
Uses - nappies

Smart polymer - dental polymer
Properties - changes colour when it is ready to take an impression of teeth

12 of 13

Problems with plastic

-crude oil is running out, so new materials will need to be found
-last for hundreds of years before they are broken down completely. So they take up valuable space
-Degradable plastics -plastics that do rot away in the soil when dumped

  • does react
13 of 13


No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »See all Crude oil, cracking and hydrocarbons resources »