Lesson 4

Do Gases Have Density?

1. Air is matter.

2. Air takes up space and the mass of air can be measured.

3. Density of air is determined by measuring the volume and mass of a plastic bottle of air and then, partially evacuating it using a simple hand vacuum pump.

4. The mass of the partially evacuated bottle is then remeasured and the difference in mass is equal to the mass of air removed from the bottle.

5. Air has relatively constant properties and its density can be measured.

6. Air is a mixture of gases., not a single, pure substance..