The mass
in grams of 1 mole of a compound is equal to the
mass in grams of the components.
Molar
Mass (Molecular Weight)
H2O
MW
= 2(1.008) + 15.999 g
AlCl3
MW
= 26.98 + 3(35.45) g
(Note:
The Significant Figures.)
So
the mass in grams of 1 mole of each compound isÉ