| 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 : | 
