Pamela S. Moy - Morgan Park High School
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Pamela S. Moy Morgan Park High School
1744 West Pryor
CHICAGO IL 60643
This activity is written for third to eighth grades or as an introduction to
the topic. Depending on how you choose to supplement the information this
miniteach may be used for higher or lower levels.
Students will become familiar with surface tension.
Students will determine if soap and heat will affect surface tension.
For all to use: One hot plate and a large beaker
For each group you intend to have:
Four small clear plastic cups
Two boxes of gem clips (paper clips)
Dishwashing liquid (just a few drops)
Black pen for labeling
1. Label four cups with A, B, C, and D.
2. Place a beaker of water on the hot plate and heat it until it reaches a
boil (be very careful it will be hot).
3. While waiting for the water to boil, fill Cup A to the brim with tap
water. Do the same for Cup B. Be sure the water in each cup is exactly
to the rim of the cup without spilling over the side.
4. Drop one gem clip at a time carefully into Cup A until you see the water
begin to seep over the side of the cup. Count the number of gem clips it
takes to cause this to occur. Record this number in a chart and describe
the dome of water building on top of the cup.
5. Now add five drops of dishwashing detergent to Cup B and allow about a
minute for it to disperse in the water. Repeat the process you used with
Cup A. Count the number of gem clips required to cause the water to seep
over the side of the cup. Record this in a chart and describe the dome
of water building on top of the cup.
6. Fill Cups C and D to the top with the water you have been heating on the
hot plate. Be VERY careful not to burn yourself with the hot water or
the hot container. Make sure you get the water level to the rim as you
did with Cups A and B.
7. Add five drops of dishwashing detergent to Cup D and allow about a minute
for it to disperse in the water.
8. Add gem clips to Cup C until water overflows. Describe the dome. Record
this information. Repeat this process for Cup D and record your results
in the chart.
Students will demonstrate the ability to work scientifically and accurately
in the lab.
Students will answer questions as to why the water looked dome-like and took
so long to overflow.
Students will make a hypothesis as to why and how the different conditions in
the water affected the surface tension.
Students should analyze error in technique that may have affected the results.
Students explore the possibilities of surface tension. They will see how
detergent and heat lower surface tension. Higher level students may explore
bonds and polarity affecting surface tension.
Walker, Pam and Elaine Wood.
"Surface Tension." Hands on General Science Activities with Real-Life
Application. The Center for Applied Research in Education.