1. Density The property of density is intensive and is the measure of the ratio of an objects mass to its volume. Density is a physical property of matter. Intensive properties - properties that is independent of the amount of material or sample size. ex: density, boiling point, freezing point Extensive properties - properties that do depend on the amount of material or sample size. ex: volume, length, mass

2. If a substance is heavy, such as water, it means that it has a high density. If a substance is light, such as a feather, it means it has a low density. 10kg of water occupies about 10L 10kg of feathers occupy a much larger volume, say 100 L

3. Density of common substances SubstanceDensity (g/cm3) Air0.001 Wood0.16 Ethanol0.79 Water1.00 Table Sugar1.59 Table Salt2.16 Iron7.9 Gold19.32

4. To calculate the density of an object you take the mass and divide by the volume. Most times the units will be g/mL or kg/L Volume can also be in m3 Practice: a. water b. feathers D = mass volume

5. If you know the density of an object and the volume you can caluclate the mass. mass = density x volume If you know the density of the object and the mass you can calculate the volume. volume = mass density