15. Solving a chemistry problem

4. In the determination of Na in NaCl, a strongly acidic cation exchanger Ku-2 in the H-form was used. A sample weighing 1.0004 g was dissolved in water in a volumetric flask with a capacity of 100 ml, the volume of the solution was adjusted to the mark with water and the analyzed solution was obtained. An aliquot of the analyzed solution with a volume of 10.00 ml was passed through a chromatographic column with an H-form cation exchanger, and after washing the column with water, the collected eluate was titrated with NaOH solution with a molar concentration of 0.1002 mol/l, while spending 17.08 ml of the titrant solution. Write the equation for the reaction of ion exchange between the cation exchanger (R-H) and the analyzed p-ohm, passed through the cation exchanger, in molecular and ionic form, calculate the mass fraction of % Na in the analyzed sample. Why is it not recommended to apply the above method in the analysis of salts containing anions of weak acids, for example, in the analysis of sodium acetate?