Planet Earth
There are six main pollutants that are detrimental to the health of humans: nitrogen oxides, sulfur oxides, ozone, carbon dioxide, lead, and particulate matter. The experiments below deal with carbon dioxide and particulate matter, and also allow children to examine convection and inversion in relation to smog. The experiments are generalized so they can be adapted for large classroom groups or just a few children.
Collect and Measure Particulate Matter
This experiment lets kids measure particulate matter that is put into the air by different vehicles. Particulates are solids that are put into the air by burning wood, fuel and coal. Once they settle, they can be inhaled, causing coughing and breathing problems. You can use as many or as few vehicles as you like, but it's educational for the kids to interview the car's owner about how old it is, its make and model, the type of fuel it uses, etc.
Cut coffee filters into 2 inch x 4 inch pieces. Glue them to index cards. Start each vehicle and let it run for 1 minute. Hold the card near the exhaust pipe as the car runs. (Be careful that children don't touch the exhaust pipe or breathe in the exhaust.) Observe the cards under a microscope or magnifying glass. The more of those little brown and black dots on the card, the more particulate matter a car is putting out. In general, if the card is completely full, it's putting out about 3,000 parts per square inch of particulate matter. If the card is fairly sparsely dotted, the car is probably putting out about 100 parts per square inch of particulate matter.
The kids can compare and contrast the vehicle outputs and determine which types of vehicles put the most particulate matter into the air.
Smog in a Shoebox
This experiment is a bit more involved and should be administered by an adult, but it allows kids to see how smog gets trapped in the atmosphere.
Lay a shoebox on its side, without the top. On the top side of the box, cut two holes just large enough for two paper towel tubes. Put the tubes in the holes and use tape to create an airtight seal. Use clay to make a sturdy base under one of the tubes, and place a candle in it. The top of the candle should be at least 2" away from the bottom of the tube. Wrap saran wrap around the open side of the box and use to tape to create an airtight seal. Use a long match to light the candle through the tube. Wait for 5 minutes. Then, crumple up a paper towel or napkin, light it on fire for about 5 seconds, and blow it out. It should be smoking. Hold it above the second tube (the one without the candle).
What should happen: The cold air from outside the box should push the smoke into the box. Once in the box, the smoke will warm back up and rise up through the tube near the candle.
Now, blow out the candle and put ice cubes down both tubes. While the box is cooling, place a heat lamp directly over one of the tubes. Don't block it, but aim the heat into the box. Again, light a paper towel or napkin on fire for a few seconds, blow it out, and drop it down the other tube. Then, cover that tube with a piece of paper.
What should happen: The warm air will move over top of the cool air and trap it in the box. After 30 seconds, you can lift the paper and the smoke will be able to escape through that tube.
How Much Carbon Dioxide Does Your Family Produce?
This quick experiment will help your child understand his or her "carbon footprint."
Obtain receipts for gasoline and propane for the past month. Record the number of gallons of each used. Use last month's utility bill to determine how many "kilowatt hours" or kph your family used and record this number. If you use natural gas, also record how many "therms" of natural gas you used in the past month. Multiply your gasoline gallons by 19, your propane gallons by 12, your "kilowatt hours" or kph by 1.8, and your "therms" by 12. Add these numbers together. This will give you a good estimate of how many pounds of carbon dioxide your family produced in the last month.
If your kids are concerned about lowering their "carbon footprint," here are some easy tips: Turn off lights when no one's in the room. Turn off the TV when no one's watching it. Turn down the heat on your water heater. Use lower wattage light bulbs. Hang clothes on a clothesline instead of using the dryer.
Tags: particulate matter, paper towel, about parts, about parts square, airtight seal, carbon dioxide
