Scot(1)
A barrel of oil
?
Crude oil is a thick, sticky liquid that is extracted from the ground. It is not very useful in this form
but it does contain many useful substances. To obtain these useful substances, the crude oil is
heated in a fractionating column, and this splits the oil into simpler mixtures called fractions. These
fractions are then used for other things.
Name of fraction
Percentage in a
typical barrel of
crude oil (%)
hydrocarbon gases
2
naphtha
13
gasoline
7
kerosene
14
diesel oil
35
lubricating oils
20
bitumen
9
1 a Use the data to draw a chart or graph to show what is in a barrel of oil.
b Explain why the method you chose in part a is the best method for displaying this data.
2 a Which fraction is the most common in crude oil?
b Which is the least common?
3 Find out two uses for each of the fractions.
4 Some fractions are in much greater demand than others. In a process called ‘cracking’ fractions
further down the list in the table can be converted into fractions higher in the list.
a Suggest the name of a fraction for which there is not enough demand and some of the
fraction may need to be ‘cracked’, Give a reason for your answer.
b Suggest the name of a fraction that may need to be produced by ‘cracking’.
21