licl dissolved in 100mL of water calculate molar concentration licl dissolved in 100mL of water calculate molar concentration Solution Molar concentration ( Molarity ) = No. Of moles of the substance ÷ vol. Of solution in L No. Of moles = mass of substance ÷ molar mass of substance . Molar mass of LiCl = 42.394 g/mol. By knowing the mass of LiCl no . Of moles can be calculated and then molarity can be calculated as. .. Molarity = No. Of moles ÷ 0.100 L .