Gas emission is the main cause of global warming all over the world. Gases such as carbon dioxide, sulphur dioxide and nitrogen oxide emitted from power stations, cars and electrical devices are known as greenhouse gases. This is because they trap heat from the sun in the atmosphere, which leads to a rise in the temperature of the Earth and therefore a change in the climate.
A major contributor to gas emmission is the car exhuast. Gases are formed as a result of the combustion of fuels such as natural gas, gasoline/petrol, diesel, fuel oil or coal, which then escape through the exhaust pipe.
The gases released include relatively harmless ones such as nitrogen and carbon dioxide however there are also some that are dangerous for the environment:
* Carbon monoxide (CO) - A colourless, odourless, radioactive gas.
* Hydrocarbons - A compound consisting of the elements hydrogen (H) and carbon (C.)
* Nitrogen oxide - A mixture.
Another gas that is extremly harmful to the surroundings is Sulphur dioxide. It is a chemical compund and its chemical symbol is SO2. It is often described as "The smell of burning sulphur." It is produced when coal and petroleum are burnt and it is a severe concern to the world around us as it leads to Acid Rain.
In order to tackle the problem the EU (European Union) has intoduced a limit to gas emission in Europe. There is currnetly a maximum level imposed on Nitorogen Oxide, Carbon monoxide and Hydrocarbons.