Topic 8 – Fuels and Earth science SPECIFICATION

Fuels

8.1 Recall that hydrocarbons are compounds that contain carbon and hydrogen only 

8.2 Describe crude oil as:

a a complex mixture of hydrocarbons

b containing molecules in which carbon atoms are in chains or rings (names, formulae and structures of specific ring molecules not required)

c an important source of useful substances (fuels and feedstock for the petrochemical industry)

d a finite resource 

8.3 Describe and explain the separation of crude oil into simpler, more useful mixtures by the process of fractional distillation 

8.4 Recall the names and uses of the following fractions:

a gases, used in domestic heating and cooking

b petrol, used as fuel for cars

c kerosene, used as fuel for aircraft

d diesel oil, used as fuel for some cars and trains

e fuel oil, used as fuel for large ships and in some  power stations

f bitumen, used to surface roads and roofs 

8.5 Explain how hydrocarbons in different fractions differ from each other in:

a the number of carbon and hydrogen atoms their molecules contain

b boiling points

c ease of ignition

d viscosity

and are mostly members of the alkane homologous series 

8.6 Explain an homologous series as a series of compounds which:

a have the same general formula

b differ by CH2 in molecular formulae from neighbouring compounds

c show a gradual variation in physical properties, as exemplified by their boiling points

d have similar chemical properties 

8.7 Describe the complete combustion of hydrocarbon fuels as a reaction in which:

a carbon dioxide and water are produced

b energy is given out 

8.8 Explain why the…