1. Activity #21 DENSITY

2. Mass How much matter is in an object
Measured in grams (g) using a triple beam balance

3. Volume How much space an object takes up The size of an object
To Measure:
Regular Objects: L x W x H
Irregular Objects: Water Displacement
Units of Measurement
Regular Objects: cm3
Irregular Objects: mL

4. Density = mass ÷ volume or D = m/v
Density is the amount of mass a material has for a given volume
In other words… how tightly packed particles (atoms) are in a substance.
Density = mass ÷ volume or D = m/v
measured in g/cm3 for solids g/mL for liquids or solids with an irregular shape

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

6. Which do you think would have the greater volume and mass? Why?
1 gram of feathers
1 gram of rock

7. Which do you think would have the greater volume and mass? Why?
1 gram of feathers
>greater volume
same mass
1 gram of rock
<less volume
same mass

8. To Calculate the Density of an Object
1- Find the mass of the object
2- Find the volume of the object
3- Divide
Density = Mass
Volume

9. The Dead Sea

10. You can tell if an object will sink, float, or suspend in water
The density of water is 1 g/mL
Sink –density is > density of water
Float- density is < density of water
Suspend- density = density of water

11. Solid substances will sink on a liquid that has less density.
Liquid substances that are less dense will float when mixed with substances that are more dense
Solid substances will sink on a liquid that has less density.
Example: plastic on water (water has a higher density than plastic so the plastic floats)

12. Find the Density of a Jolly Rancher
Find the volume by multiplying the length x width x height.
Find the mass by using a triple beam balance.
Calculate the density by dividing mass by volume.

13. Find the Density of an Irregular Object by Water Displacement
Fill your graduated cylinder up to the 60 mL mark.
Place the irregular object into the graduated cylinder and determine the difference in volume.  THIS IS THE VOLUME OF THE OBJECT.
Find the mass of your irregular object by using the tripe beam balance.
Calculate the density by dividing the mass by volume.