Define Avogadro's number. How does it relate to the masses of chemical substances?
The number of representative particles one of the substances known as Avogadro's number
The Avogadro's constant or number 6.02 x 1023 is the number of atoms of carbon in exactly 12 g of Carbon-12.
Relation of Avogadro's number to the masses of chemical substances:
One mole of hydrogen atoms = 6.02 x 1023 atoms of hydrogen (H) = 1 a.m.u
One more of hydrogen molecules = 6.02 x 1023 molecules of hydrogen (H2) = 2 a.m.u
One mole of water = 6.02 x 1023 molecules of water (H2O) = 18 a.m.u