Calculate the mass of 1 L of solution. Mass of solution=1000mL soln ×1.19 g soln1mL soln =1190 g soln (3 significant figures + 1 guard digit)Calculate the mass of HCl . Mass of HCl=1190g soln ×37.7g HCl100g soln =448.6 g HCl.Calculate the moles of HCl . ...Calculate the molarity of the HCl.