Density

Density is the amount of matter in a given unit of volume. It can be measured in grams per cubic centimeter (g/cm³). It is a measure of how tightly packed the atoms of a substance are. When we say that ice is less dense than water, we mean that the water molecules are more tightly packed when they are in the liquid state. The formula for determining density is

One always hears that muscle is denser that fat. This means that I can work out, not lose weight and still lose inches off my waist. This is because 1 pound of muscle will take up less space than 1 pound of fat.

Mass is typically measured in grams. Volume is typically measured in ml which is the same thing as cm³ (or cubic centimeters of cc. 1 ml = 1 cm³ = 1 cc)

The density of water is 1.00 g/ml. The density of some common elements are shown below:

element	density (g/cm³)	appearance
aluminum	2.70	silvery white, metallic
antimony	6.68	silvery white, metallic
cadmium	8.64	silvery white, metallic
carbon (graphite)	2.25	black, dull
chromium	7.2	steel gray, hard
cobalt	8.9	silvery gray, metallic
Copper Gold	8.92 19.3	reddish, metallic yellow, metallic
iron	7.86	silver, metallic
lead	11.3	silvery-bluish white, soft, metallic
manganese	7.2	gray pink, metallic
Nickel Platinum	8.9 21.4	silver, metallic silver, metallic
silicon	2.32	steel gray, crystalline
silver	10.5	silver, metallic
tin (gray)	5.75	gray
tin (white)	7.28	white metallic
Zinc	7.14	bluish white, metallic

Sample problem: A solid has a mass of 128 g. It is a rectangular solid 1.0 cm by 2.0 cm by 3.0 cm. What is the density of the solid and what metal is it?

One can see the usefulness of densities for determining types of metals at this web site: