12. If you have 750 mL of a 36.5 mass % HCl solution with a density of 1.15 g/mL, how many grams of HCl are there in the solution? What is the concentration of the solution in M, m, X? (Ans. 314.81 g of 11.49M HCl, 10 m, Xsolute = 0.2207, Xsolvent = 0.7792)

13. How would you prepare 250 mL of a 0.25 M H2SO4 solution from a 98% H2SO4 solution by mass with a density of 1.18 g/mL (Ans. Take 5.29 mL of the 98% solution and add water to 0.25 ml). 250mL)