Particulate Matter - What's in the Air?
Goals and Learning Objectives: To trap and observe the appearance of particles of solid matter in our air. Read and follow lab procedures, complete data forms. Students will analyze particulate matter in the air.
Materials/resources needed: Light microscope or magnifying glass, petroleum jelly (Vaseline), glass microscope slides or any clean piece of glass - the bottom of a glass jar will also work, wax pencil or marker.
You may gain access to a microscope at a local school or college campus - ask the science instructor. FF students may use the ones in the Biology lab - see me. If you absolutely can't find a microscope or a magnifying glass use your naked eye (use good light) and do the best you can.
HYPOTHESIS: Where do you think the air might be dirty? Where do you think the air is clean? Carefully write down your hypothesis (guess). Remember to use a different font or color for your responses.
PROCEDURE:
Decide on two places you would like to test your guess. For each place you would like to test make a particle trap. Make one extra trap. Make three traps total.
For each trap, you need a microscope slide or suitable glass surface. Outline a 2.5 cm x 2.5 cm square on your glass surface using a ruler and wax pencil. Put a thin layer of petroleum jelly on the slide. Leave your traps at the test place (make sure it will not be in the way and where it will not be disturbed). Leave it there for three days. Place your extra trap in a sealed container. This is your control. You will use it to compare your test sites.
After 3 days collect all your particle traps, carefully marking each one as to exactly where it was. Be careful not to touch the petroleum jelly.
Examine each particle trap with a microscope or hand lens. Be careful not to touch the lens to the petroleum jelly. Count and record all of the particles in the 2.5 cm x 2.5 cm square. Describe the types of particles found. Record the results in the table below.
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TEST PLACE
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# OF PARTICLES
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1. Control
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2. Test Site 1:
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3. Test Site 2:
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Detailed descriptions: Write a detailed description of the particles on each trap.
CONCLUSIONS: Which traps contained the most small particles of solid matter? Why do you think this site had the most particulate matter? Was your guess correct? Carefully write down your conclusions