Formula weight in chemistry the sum of the atomic weights of all atoms appearing in a given chemical formula. What is the formula weight of glucose. Such a substance is customarily represented by a chemical formula that describes the simplest ratio of the number of atoms of the constituent elements ie an empirical formula.
The general number of equivalents formula is E MWcharge number Where MW is the molecular weight of the compound and charge number is the number of proton- or hydroxide-equivalents the compound contains.
A molecular weightof a substance is the sum of all the atomic weights of all the atoms in a molecule of a molecular substance. So the mass of a mole of the atom is ma NA. But this quantity is in the unified mass unit u. Because the definitions of both the mole and the atomic mass unit are based on the same reference substance 12 C the molar mass of any substance is numerically equivalent to its atomic or formula weight in amu.