Oh, I am sorry, my bad. Here is description:
to determine the number of moles (mol) present or the molar (M or mol/L, moldm-3) concentration, where m is the mass in grams, Mr is the relative molecular mass (the mass of 1 mol of a chemical) and V is the volume in litres (L or dm3). Don’t confuse m, M, Mr and mol they represent different things.
mol = m/Mr
M = m/( Mr x V)
mol = M x V