4.11 Gas Pollution

understand the biological consequences of pollution of air by sulphur dioxide and by carbon monoxide

sulphur dioxide
- SO2 gas added in the atmosphere by:

• combustion (burning) of fossil fuels eg. coal and oil in factories.
• vehicles- the combustion of oils and petrols and gas.

-sulphur dioxide (SO2) is combined with water (H2O) and forms sulphuric acid.

-sulphuric acid is found within the water which is in the cloud and when it rains, acid rain is produced.

-acid rain affects plants and animals:

• trees and plants are 'burned' by the sulphuric acid on the surface- usually top of tree is dead.
• calcium ions and magnesium which is obtained by the roots will be leached out of the soil- plants cannot obtain magnesium or calcium- causes yellowing of leaves and plants cannot grow.
• water of the rain will flow into streams and lakes this will reduce the PH (will make the lake acidic) aluminum ions will be released which has an affect on the fish- mucus on gills of the fish will be thickened by the aluminum ions- this will reduce the fish's ability to take oxygen from water... the fish suffocates and dies.

carbon monoxide

-CO (carbon monoxide) is produced when fossil fuels such as coal or gas are burned with insufficient oxygen.

-CO combines with haemoglobin inside red blood cells and forms a molecules called carbaminohemoglobin which blocks haemoglobin from carrying oxygen- reduce oxygen circulation. it is toxic- too much CO= fatal.

-it is difficult to get CO to be released from the haemoglobin.