31. Solution to Chemistry Problem

3. 29.5 ml of sulfuric acid solution (p=1.553 g/cm3) are placed in a 1 l measuring flask, and then water is added to the mark. 22.2 ml of the resulting acid solution are consumed for titration of 25 ml of 0.5378 mol-eq/l sodium hydroxide solution. Calculate the mass fraction (%) of SO3 in the initial acid.