|What is in crude oil?
|A mixture of many different compounds
|What are alkanes?
|Saturated hydrocarbons with the highest amount of hydrogen atoms as possible in their molecules
|What is the general formula for alkanes?
|How do we separate crude oil into fractions?
|Using fractional distillation
|What are the stages of fractional distillation?
Image: fractional_di (image/jpg)
|What makes a fraction useful as a fuel?
|Lighter fractions are more useful as fuels because they ignite easier and burn well with cleaner (less smoky) flames
|What are the products of combustion when we burn fuels in a good supply of air?
|The hydrogen and carbon in the fuel are completely oxidised and produce water and carbon dioxide
|What happens if there are sulfur impurities in fuels?
|They burn to form sulfur dioxide which can cause acid rain
|What happens if we burn a fuel with insufficient oxygen?
|We get poisonous carbon monoxide as well as particles of carbon(soot) and unburnt hydrocarbons
|What happens when nitrogen reacts with oxygen at high temperatures in engines?
|Nitrogen oxides are formed, these can cause breathing problems and acid rain.
|Why is carbon dioxide called a greenhouse gas?
|It absorbs energy which is lost by radiation from the surface of the Earth
|What are biofuels?
|A renewable source of energy that could be used to replace some fossil fuels
|What can biodiesel be made from?
|Why is Ethanol a biofuel?
|It can be made from sugar in plants
|Name a potential fuel for the future