Notice that ice has a lower density than either water (freshwater) or seawater (saltwater), so it will float in them. Seawater, however, has a higher density than freshwater, which means that the seawater will sink when it comes in contact with freshwater. This behavior causes many significant ocean currents and the concern of glacier melting is that it will alter the flow of seawater -- all from the basic functioning of density.
To convert the density to grams per cubic centimeter, merely divide the values in the table by 1,000.
Density of Common Substances
|Air (1 atm, 20 degrees C||1.20|
|White dwarf star||1010|