Comparing the Effectiveness of Glycerin, Ethylene Glycol, and Propylene Glycol as Antifreeze Agents

The purpose of this experiment was to determine if glycerin is effective antifreeze by comparing the temperature change of glycerin solutions to solutions of ethylene glycol and propylene glycol. The results of this experiment can be used to determine if glycerin is a suitable non-toxic substitute to the highly toxic ethylene glycol that is currently used as antifreeze.

This experiment was conducting using 3 M, 6 M, and 9 M solutions of each of the chemicals. Ten milliliter samples of solutions were placed into test tubes that were lowered into a beaker that contained 200 mL of ice water. Salt and additional ice water were added at specific times in the experiment, and the change in temperature of the solution after 20 minutes in the ice water was recorded using a temperature probe.

After analyzing the data with 3 ANOVA tests, it was found that for the 3 M and 6 M solutions, there was no statistical difference in the mean temperature changes of the solutions, so the three antifreezes were equally as effective. For the 9 M solutions, there was a statistical difference in the mean temperature change, and glycerin was less effective than the other two chemicals. Since two of the three ANOVA tests proved that glycerin was an effective antifreeze, it was concluded that glycerin may be used as a non-toxic substitute, but further research has to be conducted before glycerin can actually be employed, due to the inconclusive results of the third ANOVA test which were caused by experimental flaws.

Research Conducted By:

Emma Burgin
Warren Mott High School

Erin Drylie
Cousino High School