|MadSci Network: Chemistry|
Hello, I might not have grasped all the subtilities, but it looks quite obvious to me : Per liter, add 0.1mol citric acid (19.212g) and 0.05mol sodium biphosphate (6.9g). Then raise the pH to 6.0 with 1M NaOH. You may also calculate, in your final solution, the concentrations of the different ions, and then add them individually (Na citrate + citric acid + phosphoric acid + monophosphate + diphosphate) but that's not how it is usually made in a lab, equiped with a pH-meter. Hope that helps
Try the links in the MadSci Library for more information on Chemistry.