1. Define mass. Mass is the amount of matter in something. Mass is
measured with a scale or balance.
2. Define volume. Volume is how much space something takes up. It is
measured with a ruler or graduated cylinder.
3. Define density and show the formula for calculating density. Density is
how much mass is contained in a certain space. The formula for density is
4. Why does changing the shape of an object have no effect on the density
of that object? Changing an object’s shape doesn’t change how much matter
is in it, nor does it change how much space it takes up; therefore it does not
change the density.
5. Aluminum is used to make airplanes. Cast iron is used to make weightlifting
equipment. Explain why the densities of these metals make them useful for
these purposes. Aluminum is not dense so you can use it to make big things
that don’t weigh a lot. Cast iron is very dense so you can use it to make small
things that weigh a lot.
6. What is the density of water? Remember for water 1g=1ml=1cm3
The density of water is 1 g/mL
7. Why does an air bubble rise to the surface of a glass of water? A bubble
rises to the top of a glass of water since it is less dense than the water.
8. Calculate the densities of the following objects. Remember to place units
after each number.
length = 6cm
width = 3cm
height = 1cm
mass = 36g
volume = 6x3x1 = 18 cm3 density = 36 g/18 cm3 = 2 g/cm3
length = 10cm
width = 5cm
height = 2cm
mass = 300g
volume = 10x5x2 = 100 cm3 density = 300 g/100 cm3 = 3 g/cm3
Object C Use the water displacement method to determine the
density of object C (silly putty).
initial water level in graduated cylinder = 25ml
final water level after placing silly putty in graduated cylinder =
mass of silly putty=8g
volume = 29 mL -25mL = 4 mL density = 8 g/4 mL = 2 g/mL
9. Which of the following materials will float on water (density 1 g/ml)?
air = .001 g/cm3 floats
corn oil = .93 g/cm3 floats
glycerine = 1.26 g/cm3 sinks
corn syrup = 1.38 g/cm3 sinks
wood = .85 g/cm3 floats
steel = 7.81 g/cm3 sinks
rubber = 1.34 g/cm3 sinks
ice = .92 g/cm3 floats
water = 1.00 g/cm3 mixes
10. Assuming the materials don’t mix, show how the materials in question
number 9 would "stack up" in a graduated cylinder.