26. Solving a chemistry problem

196. A 2.0550 g sample containing Na2SO4 was dissolved in 100 ml of distilled water. An aliquot of 10.00 ml was passed through a layer of cation exchanger in the H+ form. 10.25 ml of 0.1550 M sodium hydroxide solution was used for titration of the resulting acid. Determine the mass fraction (%) of sodium sulfate in the sample.