# Volume Definition in Science

Volume is defined as the three-dimensional space occupied by matter or enclosed by a surface. The SI unit of volume is the cubic meter (m3), but many units exist. Other volume units include the liter (L), cubic centimeter (cm3), fluid ounce (fl oz), pint (pt), quart (qt), gallon (gal), teaspoon (tsp), and tablespoon (tbls).

### Examples of Volume

Examples of volume are common in daily life:

• A student uses a graduated cylinder to measure the volume of a chemical solution in milliliters.
• Depending on the country, a baker measures liquid volumes in milliliters, fluid ounces, teaspoons, and tablespoons.
• You can purchase a quart, half-gallon, or gallon of milk.
• Many wine bottles hold 750 ml of wine.
• Gases are sold in units of volume, including cubic liters and cubic centimeters.

### How to Measure Volume of Solids, Liquids, and Gases

• Solid volume – You can measure dimensions and use formulas to find the volume of regular geometric shapes. Calculus calculates the volume of irregular shapes. The volume of a solid may be determined by its fluid displacement.
• Liquid volume – Measure liquid volume using calibrated containers. Examples include graduated cylinders and burets. Often, the volume obtained by mixing liquids is additive, but this is not always the case. The volume of miscible liquids (such as alcohol and water) may be less than the sum of the separate volumes. Also, dissolving solids into liquids doesn’t always result in additive volume.
• Gas volume – A gas assumes the volume of its container. Sometimes the volume of a gas is determined by its displacement of a liquid.

### Volume vs Mass

Volume is the amount of space occupied by a substance, while mass is how much matter it contains. Density is the amount of mass per unit of volume. It’s possible to have volume without mass, such as an enclosed vacuum.

### Difference Between Volume and Capacity

The capacity of a container is not necessarily the same as its volume. It is the interior volume of a vessel. For example, a 500-ml beaker has a capacity of 500 milliliters, but you can fill the glassware past its mark. If you measure the exterior dimensions of the container, its volume is greater than its capacity.