Ch.9 - Polyprotic Acid-Base EquilibriaWorksheetSee all chapters
All Chapters
Ch.1 - Chemical Measurements
Ch.2 - Tools of the Trade
Ch.3 - Experimental Error
Ch.4 + 5 - Statistics, Quality Assurance and Calibration Methods
Ch.6 - Chemical Equilibrium
Ch.7 - Activity and the Systematic Treatment of Equilibrium
Ch.8 - Monoprotic Acid-Base Equilibria
Ch.9 - Polyprotic Acid-Base Equilibria
Ch.10 - Acid-Base Titrations
Ch.11 - EDTA Titrations
Ch.12 - Advanced Topics in Equilibrium
Ch.13 - Fundamentals of Electrochemistry
Ch.14 - Electrodes and Potentiometry
Ch.15 - Redox Titrations
Ch.16 - Electroanalytical Techniques
Ch.17 - Fundamentals of Spectrophotometry
BONUS: Chemical Kinetics
Sections
Diprotic Acids and Bases
Polyprotic Acids and Bases
Diprotic Buffers
Polyprotic Buffers
Principal Species
Isoelectric and Isoionic pH

Polyprotic buffers deal mainly with triprotic acids and their different forms. 

Polyprotic Buffers

Concept #1: A triprotic buffer can be approached in a way similar to diprotic buffers. The key difference is that a triprotic acid has 3 pKa values. 

Polyprotic buffers usually deal with triprotic buffers. It is imperative we remember the relationships between Ka and the different forms of a triprotic acid. 

Depending on the forms used the format of the Henderson Hasselbalch equation can change.