|
Avogadro's Constant defines a mole as having a value of 6.02214129(27) x 1023, as it refers to the number of particles of a substance.
|
|
The basic correlation is that a mole is the amount of any known or unknown substance that has as many elementary entities as there are atoms in twelve grams of pure carbon-12.
|
|
That means that one mole of pure C-12 must have a mass of twelve grams in order for the unit of measurement to line up.
|
|
The number of elementary entities in any substance is known as its chemical amount, which makes the mole an easy to use unit of measurement for chemical amounts.
|
|
In chemistry, a mole is a more convenient standard unit than attempting to measure in mass or volume, especially in chemical equations.
|
|
The representation in measurement is further simplified by the concept of the molecular mass, which states that the mass of one mole of a substance (measured in grams) is equal to the molecular mass.
|
|
Therefore, one mole of a substance is equal to the molecular mass of the same substance.
|
|
The development of the mole as the standard unit of measurement for calculating the elementary entities contained within a substance has a history that dates back to the first table of relative atomic mass, crafted by John Dalton in 1805.
|
|
Later, Jons Jacob Berzelius was instrumental in redefining relative atomic mass with a greater degree of accuracy.
|
|
For some time, hydrogen and then oxygen-16 became the standard for comparison in measuring units, following the use of mass spectrometry.
|
|
Wilhelm Ostwald coined the term mole in 1894, shortened from the German word for molecule.
|
|
There has been controversy over the use of the mole as a standard unit of measurement since its formal adoption in 1971, largely because scientists have long known that knowing the mass of a substance is not always necessary for measurement.
|
|
While those who work in a chemistry field rely on the mole as a unit of measurement, its application for industry is impractical since the amount is so small.
|
|
The kilomole was introduced to define larger sample units, which is the number of entities in twelve kilograms of carbon.
|
|
As of 2011, the governing body over weights and measures agreed to investigate alternatives to the mole.
|
