| Take
a look at the two boxes below. Each box has the same volume. If
each ball has the same mass, which box would weigh more? Why?
The box that
has more balls has more mass per unit of volume. This property
of matter is called density. The density of a material helps to
distinguish it from other materials. Since mass is usually expressed
in grams and volume in cubic centimeters, density is expressed
in grams/cubic centimeter.
We can calculate density using the formula:
Density=
Mass/Volume
In the
previous lesson you calculated the mass and volume of two blocks.
If you would like to review these sections click on the appropriate
links shown at the left.
Block I
Mass = 79.4
grams
Volume=29.8
cubic cm.
Block
II:
Mass= 25.4
grams
Volume=29.8
cubic cm.
Now
Let's calculate the density for each of these blocks.
Please enter
your answer for Block I in the space provided:
If you need
a calculator one is available. Click on calculator in right frame.
Please enter
your answer for Block II in the space provided:
If you need
a calculator one is available. Click on calculator in right frame.
What is each
block made of?
Using the table
below it is now possible for you to determine what substance makes
up each block. The
densities for some common substances are:
| Substance
|
Density
(gm/cu.cm) |
| Air |
0.0013 |
| Wood
(oak) |
0.85 |
| Water |
1.00 |
| Ice |
0.93 |
| Aluminum |
2.7 |
| Lead |
11.3 |
| Gold |
19.3 |
| Ethanol |
0.94 |
| Methanol |
0.79 |
Block
I is made of:
Block
II is made of :
|
