Understanding Density and Compactness

1. Density Density How compact is the material?

2. How close the atoms or molecules are to each other More than heaviness - density includes how much space an object takes up! All substances have density including liquids, solids, and gases Density is the measure of the compactness of a material Density is the measure of the compactness of a material

3. Compactness Compactness

4. Density Density Density describes how much mass is in a given volume of a material.

5. Mass is the amount of matter in an object (usually measured in grams) Volume is the amount of space an object takes up (usually measured in ml or cm 3 )

6. Density Equation Density Equation D = m v

7. Given: mass = 1500 g; volume = 1700 mL Equation: D = m/v = .88 g/mL Solve: 1,500 g 1,700 mL = 0.8823529 g/mL A solid wax candle has a volume of 1,700 mL. The candle has a mass of 1.5 kg (1,500 g). What is the density of the candle? Word problems Word problems

8. What do you think? What do you think? If the volume stays the same and the mass increases . . . the density will If the mass stays the same and the volume increases . . . The density will

9. The units used for density depend on whether the substance is solid or liquid. For liquids use units of grams per milliliter ( g/mL) For solids use density in units of g/cm 3 or kg/m 3 . Units for density Units for density

11. Density of common materials Density of common materials Liquids tend to be less dense than solids of the same material. Ex. solder

12. Water is an exception to this rule. The density of solid water (ice) is less than the density of liquid water . Density of common materials Density of common materials