Sticky Surface Science Fair Projects

Surface Tension

What is surface tension? Surface tension is the resistance that is produced by the surface of a compound.

EDU-36820 C2D Discovery Planet Digital Microscope	Young Scientists Club Set 2	Discovery Planet EDU-41021 Maxscope Videoscope	Student, HomeSchool & Adult Microscopes
Ages 8 and up	Ages 5 - 8	Ages 10 and up	Age 10 thru College

Objectives/Goals

This project is entitled #Sticky Surface: What Affects the Surface Tension of Water the Most? Liquid Dish Soap, Salt, or Rubbing Alcohol?# The purpose of this project is to observe which solution(s) reduce water#s surface tension, or the ability of water to stick together, the most effectively. The hypothesis stated that if liquid dish soap is added to water, then the surface tension of water will be reduced because the hydrophobic ends of soap will stick out of the water and separate the water molecules from each other, causing the attraction between water molecules to weaken, thus reducing the surface tension. Water, a liquid dish soap solution, a salt water solution, and a rubbing alcohol solution will each be dripped on ten pennies until the penny overflows and the surface tension breaks. Each of the forty trials will be recorded and observations will be taken as needed. The results of these procedures were that the pennies dripped with water were able to hold an average of 1.26 mL of liquid, the pennies dripped with the liquid dish soap solution were able to hold an average of 0.60 mL of liquid, the pennies dripped with the salt water solution were able to hold an average of 1.12 mL of liquid, and the pennies dripped with the rubbing alcohol solution were able to hold an average of 0.61 mL of liquid. In this particular experiment, the liquid dish soap solution caused the most reduction of water#s surface tension, which supports the hypothesis. 3rd party contributor