Fuels

Question 1

Hydrocarbons

Answer 1

Hydrocarbons are compounds of hydrogen and carbon only

Question 2

Crude oil

Answer 2

Crude oil is a mixture of hydrocarbons, it is finite and non-renewable (it will run out)

Question 3

Homologous series

Answer 3

Homologous series is a group of compounds which have the same general formula but each compound has a different number of carbons e.g. alkanes

Question 4

Alkanes

Answer 4

Methane - CH4
Ethane - C2H6
Propane - C3H8
Butane - C4H10

Question 5

Hydrocarbons - oxygen

Answer 5

• When there is enough oxygen hydrocarbons burn completely - carbon dioxide and water
• When there is not enough oxygen they burn incompletely - carbon (soot)/carbon monoxide

Question 6

Carbon monoxide

Answer 6

Carbon monoxide is toxic

• Soot blocks chimneys and causes breathing difficulties

Question 7

Sulphur

Answer 7

Sulphur impurities in fuels burn to make sulphur dioxide which dissolves in rainwater - acid rain, this kills fish and trees

Question 8

Nitrogen

Answer 8

Nitrogen from the air burns to make nitrogen oxides which cause acid rain

Question 9

Hydrogen

Answer 9

Hydrogen is a renewable fuel but it is harder to store than petrol

Question 10

Cracking

Answer 10

Cracking is breaking long chain hydrocarbons in to shorter more useful ones