Volume

Measuring the volume of a liquid is relatively straight forward. Since liquids take the shape of the container in which they are placed, a liquid whose volume is to be found can simply be poured into a graduated container, that is, a container on which some scale has been etched. Graduated cylinders of various sizes, ranging from 10 ml to 1 l are commonly available in science laboratories for measuring the volumes of liquids. Other devices, such as pipettes and burettes, are available for measuring exact volumes, especially small volumes.

The volume of a liquid is only moderately affected by pressure, but it is often quite sensitive to changes in temperature. For this reason, volume measurements made at temperatures other than ambient temperature are generally so indicated when they are reported, as V = 35.89 ml (95°F; 35°C).

The volume of gases is very much influenced by temperature and pressure. Thus, any attempt to measure or report the volume of the gas must always include an indication of the pressure and temperature under which that volume was measured. Indeed, since gases expand to fill any container into which they are placed, the term volume has meaning for a gas only when temperature and pressure are indicated.