An introduction to the concept of density including how to calculate density and compare densities of different substances.
• Students will be able to define density as mass divided by volume.
Students will be familiar with the common units for mass and volume.
Students will be able to calculate density if given mass and volume.
Students will be able to compare the densities of substances to the known density of water.
Students will recognize the importance of the density of ice as compared to liquid water.
If you have ever been in a crowded movie theater or shopping mall, you are familiar with the idea of density. Picture your school classroom with only five students in it. Now think of that same classroom with 30 students in it. The classroom is the same size in each case, but the number of people is different. Which classroom situation has a higher density? If you said the class of 30 students, you are correct. More students in the same sized space means a higher population density.
In chemistry, density is a physical property of matter. Density depends on both mass and volume. The equation below shows this.