3. The pKa values for successive ionization of phosphoric acid are 2.15, 7.21, and 12.35. (a) What weights of NaH2PO4 and Na2HPO4 would be required to prepare 1 L of a buffer solution of pH 7.45 that has an ionic strength of 0.100? (b) Write the equation that specifies that the solution is electrically neutral. (c) Calculate the concentrations of all species in the buffer.
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We want to prepare a buffer solution with a pH of 7.45. Since the pKa values for successive ionization of phosphoric acid are 2.15, 7.21, and 12.35, we should use the second ionization (pKa = 7.21) to prepare the buffer. This means we will use the HPO4^2- and Show more…
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