| define fuel | a fuel is something that releases energy when burnt |
| give an example of 2 fuels | coal and hydrocarbons |
| what happens when fuels are combusted | the carbon and hydrogen atoms react with oxygen and become oxidised |
| how can you tell complete combustion has taken place | when CO2 is produced |
| what other gases can be produced | carbon monoxide, sulfur dioxide, water vapour, nitrogen oxides |
| why do many homes have carbon monoxide detecters | it is a toxic colourless gas with no smell |
| what is released when coal is burnt and why | sulfur dioxide, coal contains atoms of the element sulfur that become oxidised |
| where are oxides of nitrogen produced | in engines e.g. car engines |
| what causes oxides of nitrogen to be produced | high temps cause nitrogen and oxygen to react |
| why do scientists represent oxides of nitrogen as NOx | there's a range of different oxides that can be produced which represents the x |
| what are the main problems with SO2 and NOx's | -they can cause breathing problems in humans
-they dissolve in rain to form acid rain which damages trees and corrodes buildings made from limestone |
| what actually is soot | particulates of carbon |
| what type of pollution are unburnt hydrocarbons and soot | pollution particulates |
| what are the affects of pollution particulates on humans | increases risk of heart and lung diseases |
| what affect does pollution particulates have on the earth | they reduce the amount of energy from the sun that reaches the earths surface causing global dimming which may have an affect on rainfall patterns |
