identify the sources of pollution which accompany the combustion of organic compounds and explain how these can be avoided
The burning of fossil fuels is responsible for much of the air pollution produced by humans. Matter such as ash and soot, unburned hydrocarbons, carbon dioxide, carbon monoxide, water, sulfur dioxide and nitrogen oxides are common products of combustion and are mainly produced in power stations, factories, motor vehicles and heaters.
Carbon monoxide is formed when fossil fuels are burnt under conditions favouring incomplete combustion. Even small amounts of carbon monoxide will reduce the amount of oxygen carried in bloodstreams of animals and humans.
The production of carbon monoxide can be avoided through adequate supply of oxygen during combustion. This lack of oxygen is particularly a problem in areas of high traffic density such as city centres, tunnels and carparks. Using more fuel-efficient vehicles and more public transport will help reduce the production of carbon monoxide.
Sulfur dioxide and occasionally H2SO4 are products of burning fossil fuels containing small amounts of sulfur. During the combustion process, sulfur is converted to sulfur dioxide (SO2) - a heavy and colourless gas.
S (in fuel) + O2 (g) → SO2 (g)
Sulfur oxides formed can dissolve in atmospheric water to form an acidic haze of sulfurous and sulfuric acid. In extreme cases, an unpleasant smog can form if high levels of smoke are present.
Emissions of sulfur dioxide can be avoided through the use of low-sulfur fuels, reducing sulfur content of fuels before combustion and removing sulfur oxides from atmospheric emissions.
Photochemical smog often occurs on warm and sunny days when the air is still. It occurs through a series of reactions involving unburned hydrocarbons and nitrogen oxides. Unburned hydrocarbons in petrol are released into the atmosphere by vehicles and nitrogen oxides...