Eat Your Experiment
F. Lee Slick
Purpose: This experiment is designed for Chemistry or Physics students. If you like to eat in class, this experiment is for you. Now if you can't cook you are in trouble. Follow directions carefully and you will not have too many problems. This is a good way to demonstrate rate of reaction of an event, and graphing of data.
In order for you to do this experiment, you need to be able to count. Starting with a pile of popcorn beginning with 200 kernels of popcorn. You must keep track of the number of kernels, because you will be ask questions about it later. A 2 pound coffee can works quite well for a container to pop the corn in. However a 1000 ml beaker will also work but you have to clean this up when you are finished. Be sure to keep the lid from the coffee can, but you must put slits in the lid, otherwise the can will explode. Add to base of the container a small amount of popcorn oil, or cooking oil, not butter. If you use the 1000 ml beaker, you will need to cover the top with an aluminum foil with holes in it. Now set up a data table with the following information. column 1 contains the number of pops, column 2 contains the time in seconds. Columns must be uniform. Now you need a Bunsen burner, ring stand, ring holder and wire gauze or hot plate. Start heating (slowly) and make note of the time when the first pop occurs, keep track of the time you started. You must be able to count very fast listening for the pops and count the number of pops every 3 to 5 seconds. Continue counting until there are no more pops, immediately remove the can or beaker from the heat (BE CAREFUL NOT TO BURN YOURSELF). Now the fun begins, if you didn't burn the popcorn, proceed to eat it keeping track of every popcorn piece. (Salt is available) Count all kernels that did not pop and record this. If you burned your popcorn you must do the experiment over. Your instructor will test your popcorn for eat ability by sampling your experiment. Now analysis time, add a third column to your data table and carefully add up all of the pops. When you have finished your column you should be able to tell me the number of kernels that have pop at the end of 20 seconds, or 25 seconds, or 30 seconds, etc.. Time to check out your graphing skills. Take a full sheet of graph paper and do the following. Draw a vertical and horizontal line as close to the left edge and bottom of the sheet of graph paper. (approximately 2 cm in from the left edge and 2 cm up from the bottom. ) Label the vertical " Total number of pops" (PRINT) and the horizontal "Time in seconds" (PRINT). At the top of the graph , be sure to print your name and the class as well as the period. (Example "A Bright Student" "Chemistry period 3") Did you draw the line with a ruler? If not deduct 20% from your grade. Proceed to plot "Total number of pops " vs. "Time in seconds" and draw in a smooth curve. Now answer the following questions:
|Number of Pops||
Time in seconds
|Total Number of Pops|
|. . .|
LIST OF MATERIALS:
200 kernels of popcorn
popcorn oil or cooking oil
coffee can and lid or 1000 ml beaker and foil (BE SURE THAT IT IS CLEAN)
graph paper, ruler and pencil
Bunsen burner or hot plate
EXAMPLE OF GRAPH
Questions and Problems for your consideration:
If you have not plotted a graph of "Total number of pops vs. Time" do so at this time and answer the following questions:
What can you conclude from the graph?
What does the graph show?
Do you see a linear relationship? What is the rate of reaction? Try taking the slope of the linear relationship.
Why didn't all the corn pop?
I f you burned your experiment, do it over, if you did not burn your experiment. I'll help you eat it. When eating be sure to count the number that have popped.
Where there an equal number of pops in each time interval?
What do you think would have happened if you had used 500 kernels instead of 200? (referring to the graph)
When you are done, be sure to clean up your mess.