C9 Crude Oil and Fuels – Aiming for 4

Tasks

1The following table contains information about how crude oil was formed. Thestatements are in the wrong order.

Number the statements (or cut them out and stick them on a new piece of paper) in the correct order.

Each statement has an empty box next to it. Draw a picture of what happens to help you remember each step. (3 marks)

Crude oil eventually forms.
Silt and mud cover them.
Extra layers of rock build up on top over millions of years.
The temperature and pressure get very high.
Dead animal and plant remains fall onto the seabed and river beds.

2Alkanes are types of hydrocarbons. This means they only contain carbon and hydrogen bonded together. Each atom in an alkane is held together by a single bond.

Alkanes are given names that tell us how many carbon atoms they contain. The carbon atoms form a chain.

  • The start of the first five alkane names are as follows:

‘Meth’ if it contains 1 carbon atom.

‘Eth’ if it contains 2 carbon atoms.

‘Prop’ if it contains 3 carbon atoms.

‘But’ if it contains 4 carbon atoms.

‘Pent’ if it contains 5 carbon atoms.

  • The ending of all alkanes is always ‘ane’, like in alkane.
  • When the chain is drawn out, the carbons are linked together. Each carbon has two hydrogen atoms bonded to it (drawn above and below the carbon). There are two extra hydrogen atoms,one at each end of the chain.

Complete the following table by drawing and naming the first five alkanes. The first box has been partly completed to help you. (15 marks)

No. of carbons in chain / Name of alkane / Diagram / Description
1 / m___ane / / One carbon atom. There are four hydrogen atoms bonded to the carbon.
2
3
4
5

3Alkenes are another type of hydrocarbon. They also contain just carbon and hydrogen atoms.

  • They are different from alkanes because they contain a double bond – there are two bonds between the carbon atoms instead of one.
  • The beginning of the names of alkenes is the same as for alkanes.
  • The ending of alkenes is ‘ene’, like in alkene.
  • For example, ethene contains two carbons double bonded together:

It is possible to find out whether a substance is an alkane or an alkene by adding a substance called bromine water.

Your teacher will show you how to set up the apparatus for testing alkanes and alkenes with bromine water, and how to add the bromine water to eachone.

Complete the following table as you carry outyour experiment:(2 marks)

Substance being tested / Colour of bromine water before being added / Colour of bromine water after being added
alkane
alkene

Now complete the following paragraph, choosing from these words – you can use them more than once if you need to:

colourless react alkenes orange double bonds

Bromine water has an ______colour.When it is added to alkanes it remains ______. When it is added to alkenes it becomes ______. This is because the bromine water reacts with ______. Only ______have a double bond, so only they ______with bromine water. (6 marks)