After all this was set-up we kept on adding pennies to the left side of the balance until the right side rose above the water totally. We repeated this five times and found out it took 11 to 12 pennies to raise the right side above the water. We stirred it in and repeated the experiment five more times and recorded our results on a graph again. We then compared both results using the graphs. The results of our project tells us that soap does affect surface tension.
Soap makes it easier to lift the plastic pan from the water.
The reason why it does this is because soap spreads out the molecules, causing the surface of the water to be thinner. Surface tension causes liquids to act like a thin, elastic film. Surface tension is caused by cohesion, a force that causes the molecules of a substance to be attracted to one another. Molecules of a liquid that are below the surface have molecules pulling on them from different directions. But the molecules on the surface are attracted only by the molecules below and to their sides.