[lnanglet]

Sports Drinks contain NaCl, Citric Acid, and various forms of sodium and potassium citrate and phosphate.
Although gatorade/powerade are not a pure solutions of citric acid and phosphoric acid, assume it is. There are no other components except citric acid  and phosphoric acid for this calculation.

Assume you are titrating a mixture of citric acid and phosphoric acid. You know the formal concentrations of each (Ca). You add some NaOH as a titrant. a) assuming you know the volume that both acids have been dissolved in (Va) and the volume (Vb) and concentration (Cb) of the base.

a) Write the charge balance on this solution
b) Using the info above,, derive an equation that could be used to calculate [Na+] added to the solution. This equation would include the variables.

Please help I have been looking at this for a week and I just can't figure it out.