1. Density What is density?
What is the formula for calculating density?
What are the units for density?
Density is the amount of mass a material has for a given volume
The formula for density is: Density = mass ÷ volume or D = m/v
The units for density are g/cm3 for solids g/mL for liquids or solids with an irregular shape

2. Density Less dense More dense Less mass (matter) in a given volume
More mass (matter) in a given volume

3. Which would have the greater volume, a gram of feathers or a gram of rock?

4. A gram of feathers would have greater volume because feathers have a low density. It takes a lot more feathers to make a gram.
1 gram of feathers
greater volume
1 gram of rock
less volume

5. Which would have a greater mass, a gram of feathers or a gram of rock?

6. A gram is a gram! Both substances would have the same mass.
1 gram of rock
same mass
1 gram of feathers
same mass

7. Density
Density is a measure of how tightly packed and how heavy the molecules are in an object.
Which picture shows a substance with lower density (less dense)?
Which picture shows a substance with greater density (more dense)?
Density is the amount of matter within a certain volume.

8. Density
Does ice have the same density as water?

9. Density Ice and water have different densities!
Ice is less dense than liquid water. We can see the difference in the picture to the right.
The less dense ice cubes float on top of the more dense water

10. How do you calculate density?
1- Find the mass of the object in grams (use a triple beam balance)
2- Find the volume of the object in mL by using water displacement
3- Divide!
Density = Mass
Volume

11. Example problem A piece of metal has a mass of 35 grams
The volume of the metal is 7 cm3
Divide to find the Density
Density = mass/volume
Density = 35g / 7cm3
Density = 5 g/cm3
Density = mass/volume
Density = m ÷ v
D = m/v
D = m ÷ v

12. The density formula
The density formula can be rearranged to find Density, mass, or volume
To find Density: D = m ÷ v To find mass: m = D x v To find volume: v = D ÷ m

13. The Magic Triangle m = mass v= volume D = density
m = D x v v = m ÷ D D = m ÷ v