Proving Density - Mathematically
by Pam Collinge
January 23, 2009
“Seeing is believing” and sixth grade science students could see that when water, alcohol, and vegetable oil were poured into a graduated cylinder, the liquids separated into three distinct columns according to their density. The challenge this week was to apply the formula of Mass/Volume=Density to the liquids to see if the different densities could be proven mathematically. Students used a balance to find the mass of the liquids measured in grams and a graduated cylinder to find the volume of each liquid measured in milliliters or cubic centimeters. They divided these two measurements to find the density of the three liquids in cm3. Results were charted, graphed and compared. In conclusion, students were able to prove that water was the most dense, followed by oil and then alcohol. It was decided that density could be used as a characteristic property of matter and some students were ready to try the formula on some of their jewelry to see how it compared to the density of gold.
