Please check your Internet connection and reload this page. If the problem continues, please let us know and we'll try to help. An unexpected error occurred. Previous Video 1. This system defines seven base units for length, mass, time, temperature, amount of substance, electric current, and luminous intensity. These are called the Standard Units. Units of measurements which are a combination of one or more base units are known as the derived units.
Two of the most commonly used derived units in chemistry are volume and density. Volume is a measure of the space occupied by an object. The SI unit for volume is defined by the base unit of length, the meter.
Thus, any unit of length, when cubed or raised to a power of three, becomes a unit of volume. For example, m 3 , cm 3 , and mm 3 , are all units of volume. Density, on the other hand, is the ratio of the mass of a substance to its volume. Thus the units for density are defined by the base units of mass and length. Standard and derived measurements are very helpful in defining various properties of matter. These properties can be broadly divided into two groups — intensive and extensive.
When the property is independent of the amount of matter present, it is known as an intensive property. Temperature, density, boiling and melting point, odor, and hardness are examples of intensive properties.
The density of tin, for example, is 7. Hence, a density of 7. In fact, all intensive properties can be used to identify a substance, as these characteristics do not change with the amount of, or conditions of, the sample. An extensive property, on the other hand, depends on the amount of matter present. Mass, volume, and length are all extensive properties. Extensive properties change with the sample size or conditions. This makes them a poor tool for identifying substances. The mass of a sample, for example, will not be helpful in identifying it as tin.
The International System of Units or SI system, by international agreement, has fixed measurement units for seven fundamental properties: length, mass, time, temperature, electric current, amount of substance, and luminosity. These are called the SI base units. Units of measurement derived from the mathematical combination of SI base units are called SI-derived units. Miles per hour is also considered a derived unit, even though the base units are not SI units.
In general, any derived unit is a combination of other units. Volume is the measure of the amount of space occupied by an object. The unit of length defines the unit of volume. The SI-derived unit of volume is a cubic meter m 3 , a cube with an edge length of exactly one meter. To dispense a cubic meter of water, we could build a cubic box with edge lengths of exactly one meter. This box would hold a cubic meter of water or any other substance. There are seven base units in SI system of units and unit of volume is not one of them.
Cubic centimeters, liters, gallons are three common units used for measuring volume. Also, the most popular volume units in the metric system are millilitres and litres.
Related Articles. Image made using canva app. What is the SI base unit for volume? What units are used for volume? Previous Post What is the unit of measurement for light in photography? Table 1. SI base units SI base unit Base quantity Name Symbol length meter m mass kilogram kg time second s electric current ampere A thermodynamic temperature kelvin K amount of substance mole mol luminous intensity candela cd.
SI derived units Other quantities, called derived quantities , are defined in terms of the seven base quantities via a system of quantity equations. The SI derived units for these derived quantities are obtained from these equations and the seven SI base units.
Examples of such SI derived units are given in Table 2, where it should be noted that the symbol 1 for quantities of dimension 1 such as mass fraction is generally omitted. Table 2. Table 3.
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