Phosphoric acid, H3PO4, is a triprotic acid with the following acid dissociation constants: Ka1 = 7.5 × 10-3 Ka2 = 6.2...

Question

Question

Phosphoric acid, H3PO4, is a triprotic acid with the following acid dissociation constants:

Ka1 = 7.5 × 10-3 Ka2 = 6.2 × 10-8 Ka3 = 4.2 × 10-13

Which of the following combinations would be best for preparing a pH 7 buffer?

a. H3PO4 and NaH2PO4

b. H3PO4 and HCl

c. Na2HPO4 and Na3PO4

d. NaH2PO4 and Na2HPO4

e. H3PO4 and Na3PO4

Answer 1

Answer #1

The combination of the Monosodiumphosphate (NaH₂PO4) and disodium phosphate (Na₂HPO4) is the best for prepuning a pH=7 butten

Answer 2

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