I don't know what I am doing wrong, please help!! Homework is due at midnight.
Phosphoric acid is a triprotic acid with the following pK_a values: pK_u1 = 2.148 pK_u2 = 7.198 pK_n3 = 12.375 You wish to prepare 1.000 L of a 0.0500 M phosphate buffer at pH 7, 500. To do this, you choose to mix the two salt forms involved in the second ionization, NaH_2PO_4 and Na_2HPO_4, in a 1.000 L volumetric flask and add water to the mark. What mass of each salt will you add to the mixture?