When is it helpful to use density?

If you do not know which material you have, knowing the density can help you identify it. Examples: Solid - water - noble gas

Copper has a density of 8950 kg/m3 = 8.95 kg/dm3 = 8.95 g/cm3.

Water has a density of 1000 kg/m3 = 1000 g/L = 1.000 kg/dm3 = 1.000 kg/L = 1.000 g/cm3 = 1.000 g/mL.

Helium has a density of 0.1785 kg/m3 = 0.1785 g/L = 0.0001785 kg/dm3 = 0.0001785 kg/L =

0.0001785 g/cm3 = 0.0001785 g/mL.