When a formula mass of an ionic compound is determined by the addition of its component relative atomic masses and expressed in grams it is called the molar mass.
The mass of one mole of an element or compound is called it molar mass (symbol M). There is a quantity that relates to the number of particles in a mass of substance.
Molar Mass Formula is expressed as
The molar mass is the sum of atomic masses and it must be known to determine a molecular formula from the empirical formula.