Phosphoric acid is a triprotic acid with the following pKa values: pKa1=2.148 pKa2=7.198 pKa3=12.375 You wish...

Phosphoric acid is a triprotic acid with the following pKa values:

pKa1=2.148 pKa2=7.198 pKa3=12.375

You wish to prepare 1.000 L of a 0.0200 M phosphate buffer at pH 7.720. To do this, you choose to mix the two salt forms involved in the second ionization, NaH2PO4 and Na2HPO4, in a 1.000 L volumetric flask and add water to the mark. What mass of each salt will you add to the mixture?

mass NaH2PO4= ________g mass Na2HPO4= __________g

What other combination of phosphoric acid and/or its salts could be mixed to prepare this buffer? (Check all that apply).

H3PO4 and NaH2PO4

H3PO4 AND Na2HPO4

H3PO4 and Na3PO4

NaH2PO4 and Na3PO4

Na2HPO4 and Na3PO4

Expert Solution

queen_honey_blossom answered 1 year ago

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