18-5 Biological Amines and the Henderson- Hasselbalch Equation Henderson-Hasselbalch equation Used to determine relative concentrations of amines and their conjugate acids A PH =pK.+logTHA]Henderson-Hasselbalch equation • Used to determine relative concentrations of amines and their conjugate acids             a a - - A pH = p + log HA A log = pH - p HA K K 18-5 Biological Amines and the Henderson￾Hasselbalch Equation