Revision

Question 1

Biofuels (ethanol)

Answer 1

Fermentation of sugars
Renewable
Carbon neutral
Requires lots of land
Uses lots of energy

Question 2

Biodiesal

Answer 2

From vegetable oil
Biodegradable
Renewable
Requires lots of energy
Higher NOx emissions

Question 3

Hydrogen

Answer 3

Electrolysis of water
H2O the only product
Can be piped to houses
Requires a high pressure fuel tank
Requires lots of energy

Question 4

CO2

Answer 4

Complete combustion
Greenhouse gas –> global warming

Question 5

CO

Answer 5

Incomplete combustion
Toxic

Question 6

Unburnt hydrocarbons

Answer 6

Incomplete combustion
Photochemical smog
Respiratory irritants

Question 7

SO2

Answer 7

Sulphur impurities in fuel being oxidised
Acid rain

Question 8

Nox

Answer 8

N2 and O2 from the air react due to high temperature in the engine
Acid rain
Respiratory irritant
Photochemical smog

Question 9

Enthalpy change of combustion

Answer 9

Enthalpy change when one mole of a substance is completely combusted under standard conditions

Question 10

Enthalpy change of neutralisation

Answer 10

Enthalpy change when one mole of water is formed when an acid and alkali react under standard conditions

Question 11

Enthalpy change of formation

Answer 11

Enthalpy change when 1 mole of a substance is formed from its elements under standard conditions