Practice: Determine the pH of 0.250 M sodium phosphate, Na3PO4. Phosphoric acid, H3PO4, contains Ka1 = 7.5 × 10−3, Ka2 = 6.2 × 10−8 and Ka3 = 4.2 × 10−13.
TRiprotic Acids and Bases require ICE Charts to determine their pH and pOH respectively
Concept #1: The acidic form of a triprotic acid has its pH solved in a similar way to monoprotic acids.
Example #1: Determine the pH of a 0.225 M phosphoric acid, H3PO4, solution. Ka1 = 7.5 x 10-3, Ka2 = 6.2 x 10-8 and Ka3 = 4.2 x 10-13.
Practice: Determine the pH of 0.250 M sodium phosphate, Na3PO4. Phosphoric acid, H3PO4, contains Ka1 = 7.5 × 10−3, Ka2 = 6.2 × 10−8 and Ka3 = 4.2 × 10−13.
Practice: Determine the pOH of 0.450 M citric acid, H3C6H5O7. It possesses Ka1 = 7.4 × 10−4, Ka2 = 1.7 × 10−5 and Ka3 = 4.0 × 10−7.
