how many particles in 1 mole of substance
Answers
In science, we have a name for this, called Avogadro's number, and it describes the number of representative particles in one mole of a substance.
Avogadro's number is
6.022
×
10
23
l
mol
−
1
−−−−−−−−−−−−−−−−−
The inverse mole unit tells us there are
6.022
×
10
23
particles of something *per mole*.
The official definition of the mole is the quantity that describes the number of elementary entities as there are atoms in
12
g
of isotopically pure carbon-12.
From this definition, we see that
1
mol
of pure
12
C
has a mass of exactly
12
g
. The mass of a substance in one mole of that substance is called the molar mass of that substance.
To find the number of moles of a substance present, we divide the mass of the substance by its molar mass, which we see from the definition of molar mass:
molar mass
=
mass
mol
mol
=
mass
molar mass