Density Lesson
Name_____________________class______
Read and highlight important information then answer the questions. Show your work!
If you have ever been in a crowded movie theater or shopping mall, you are familiar with the
idea of density. Picture a classroom with only 5 students in it. Now think of that same
classroom with 30 students in it. The classroom is the same size in each case, but the number
of people is different. Which classroom situation has a higher density? If you said the class
of 30 students, you are correct. More students in the same sized space mean a higher
population density.
In science, density is a physical property of matter. It is the amount of matter in an object
(the students) compared to the amount of space it takes up (the classroom). Density
depends on both mass (amount of matter) and volume (amount of space).
Density = mass ÷ volume
or
mass/volume
Remember, mass is how much matter is in an object and you use a scale or balance to find
mass. Volume is the amount of space that an object occupies. Since density includes volume,
fill in the review on finding volume.



To find the volume of a liquid just pour it into a ______________ ________________ and
read the units _____________ level.
For volume of a regular shaped object (box) multiply _________ x _________ x _________
To find the volume of odd shaped objects use water _______________________________
Density can be calculated by taking the mass (usually measured in grams) and dividing
it by the volume (usually measured in cm3 for solids or mL for liquids).
Imagine the following experiment. You have a block that is 2cm long by 2cm wide by 20 cm
high. This means that the volume ( L x W x H ) of the block is _______cm3. You place the
block on a balance and find that its mass is 50 grams. You would calculate the density of the
block by taking 50 g and dividing it by 80 cm3. The density of the block is _______ g/cm3.
The density of many common substances is known. For example, the density of water is
1.00 g/mL. The density of a substance determines whether that substance will sink or float
if placed in a liquid like water. Substances that are less dense than water will float on its
surface and substances that are denser will sink in it.
 Gold has a density of 19.3 g/cm3, which means it will __________ in water.
 A certain type of wood has a density of .6 g/cm3 so it will _________ in water.
You can try a simple experiment involving the density of liquids at home. Take a glass of
water & pour some vegetable oil on top of the water. You will notice that the oil forms a layer
on top of the water. Why would this be? ______________________________________
Density Questions
Write True or False, then answer the rest showing all your work.
 1.You can observe the concept of population density in a movie theater.
 2. If there are five people in a store at the mall and then 10 more people come in, the store
become less dense.
3. What two things does density depend on? ___________ and __________
4. Mass is usually measured in _______.
5. If you have something with a mass of 20g and a volume of 5cm3, what is that object’s density?
a. 25g/cm3
b. 15g/cm3
c. 4g/cm3
d. .25g/cm3
6. What is the density of water? ______
7. Would a liquid with a density of 2g/cm3 sink or float when added to water? ________
8. Ice _______ in water.
9. As water freezes it becomes _________ dense (think about ice in your drink).
Volume of a solid = L x W x H or water displacement
Density = Mass(g) / Volume(cm3)
10. What is the density of an object with a mass of 60g and a volume of 2cm3?
11. You are given the following information: mass = 48g; volume=24cm3. What is the density of this
substance?
12. If you have a rectangular gold brick that is 2cm by 3cm by 4cm and has a mass of 48g, what is its
density?
13. Bob, who weighs 150 pounds, found a rock. What is the density of a rock if its mass is 36 g and
its volume is 12 cm3?
14. An object is put in a graduated cylinder with 20ml of water. It rises up to 30ml. When the
object is put on the scale is 150 grams. What is the density of this object?