Science 6th grade | UNIT 2: Living things and environment 2.6 Air pollution
Our atmosphere consists mainly of two gases: nitrogen and oxygen. There are smaller amounts of carbon dioxide and water vapour. None of these gases are harmful. But people pollute our atmosphere with particles of other gases.
Carbon monoxide is poisonous. New cars are less polluting than older ones because they are fitted" with a device that changes the exhaust gases into carbon dioxide.
We burn coal and oil to give us energy. Wind power, solar power and water power do not cause pollution, but for many countries they are more expensive than coal or oil.
Sometimes pollutants are blown away by the wind. But often dirty air lies over cities. Pollution has a negative effect on plants and animals. People in polluted areas often get bronchitis and asthma.
give off the gases sulfur dioxide and nitrogen oxide. |
off carbon monoxide in exhaust fumes. |
Activity 2.6 (Measure dirt particles in the air)
You will need: five glass slides - petroleum jelly - a marker pen tape - a hand lens
Mark an area of 4 x 1 cm with a marker pen on one side of each slide. Number the slides 1 to 5.
Cover the other side of each slide with a thin layer of petroleum jelly.
Tape the slides to five different sites. The petroleum jelly must face outwards. Choose sites where your slides will not be disturbed. Leave these slides for one week. Then carefully put the slides in a box and bring them to school. Do not to touch the petroleum jelly.
Predict which slide is going to have the most pollution. Give reasons. Examine each slide with a hand lens. Can you see particles of dirt?
Count the number of particles in each marked area.
Record your results on a table. Draw a bar chart of your results.
Questions
1) Compare your results with other groups. Which site is most polluted? Can you explain why?
2) Identify the pattern in your results. Did any sites not fit the pattern that you expected?
3) Did the evidence you collected support your predictions?
4) Work in a group to produce an information leaflet on another type of pollution. You could choose water or land pollution. Present your information to the class.