Calculate the ratio of the molar concentrations of HPO42- and H2PO4- ions required to obtain a buffer solution at pH = 7.0. For phosphoric acid, Ka1 = 7.5 × 10-3 Ka2 = 6.2 × 10-8 Ka3 = 4.2 × 10-13
Added by Angela R.
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1) We need to calculate the molar concentration of HPO42- ions. Ka1 = 7.5 × 10-3 ? Ka2 = 6.2 × 10-8 ? Ka3 = 4.2 × 10-13 2) We need to calculate the molar concentration of H2PO4- ions. H2PO4- (aq) = 2 moles H2PO4 (l) = 1 mole Ka1 = 2 × 10-3 ? Ka2 = 6.2 × Show more…
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Another buffer found in blood is based on the equilibrium between dihydrogen phosphate and monohydrogen phosphate. The reaction is shown below: H2PO4-(aq) + H2O(l) → H3O+(aq) + HPO42-(aq) If the pH of a blood sample was 7.23, what would you calculate as the ratio of [H2PO4-] to [HPO42-]? (Ka1 = 7.5 × 10-3, Ka2 = 6.2 × 10-8, Ka3 = 3.6 × 10-13)
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