Mole Term Origin
Name: Julie R.
How or Why is the term "mole" used as the unit for
For a given molecule, one mole is a mass (in grams) whose number is
equal to the atomic mass of the molecule. For example, the water
molecule has an atomic mass of 18, therefore one mole of water weighs 18
grams. An atom of neon has an atomic mass of 20, therefore one mole of
neon weighs 20 grams. In general, one mole of any substance contains
Avogadro's Number ( 6.02 x 10^23) of molecules or atoms of that
substance. This relationship was first discovered by Amedeo Avogadro
(1776-1858) and he received credit for this after his death. I hope that
this is helpful.
The question asks about the origin of the term "mole." The word "mole" has
nothing to do with the animal that burrows under the ground.
Mole is the English version of the German word "Mol" which is short for
Molekulargewicht, the "molecular weight."
Back about 200 years ago scientists were trying to figure out what
substances were made of. They first worked on gases and gas molecules, and
got that figured out pretty well. Then they worked on the atoms and
molecules that make up solid substances. They needed a unit of measure
that connected the mass of a molecule or atom with how many of them there
were. They settled on Avogadro's number being useful.
The terms mole, gram formula weight, and gram molecular weight all mean the
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Update: June 2012