The units of density are normally expressed as g/ml or g/cm3. (A ml and a cm3 are different expreessions of the same unit, 1ml =1 cm3 ).
The density of a liquid can be determined by weighing a known volume of the liquid. For example, to determine the density of a sodium cholride solutions, first, weigh a clean, dry 10.0ml graduated cylinder by using a digital balance. Next, sodium chloride solutions is added to the graduated cylinder and it is reweighed. The volume of sodium chloride solutions in the graduated cylinder is recorded by reading the level of liquid in the cylinder at the bottom of the meniscus.