2. What is Density? Objects with the same volume but different mass have different densities. Density is a characteristic property of a substance. The density of a substance is the relationship between the mass of the substance and how much space it takes up (volume). The mass of atoms, their size, and how they are arranged determine the density of a substance.

3. Density Density: the mass per unit volume of a substance. or how closely "packed" or "crowded" the material appears to be Mass is a measure of how much matter an object has. Weight is a measure of how strongly gravity pulls on that matter. So…….. If you were to travel to the moon your weight would change because the pull of gravity is weaker there than on Earth but, your mass would stay the same because you are still made up of the same amount of matter.

4. Ex: oil vs. water Ex: wood vs. iron Ex: ice vs. water  Density units come from units used for mass and volume: g/mL, kg/m 3, g/cm 3, etc. Density

5.  What if mass or volume is unknown? D=m/V D V m m = DV V = m/D

6. If you mix What will happen ? Why Will the THICK Fuel Oil Float?

7. Density Ex 1: What is the density of a liquid that has a volume of 25 mL and a mass of 52.2 grams? Would this liquid sink of float in water? Ex 2: What is the mass of a 100. cm 3 piece of aluminum (D = 2.70 g/cm 3 )? Ex 3: What volume would 15.7 grams of mercury occupy? (D = 13.6 g/mL)