In chemistry, the<unk><unk>  (frequently misspelled<unk> -Hasselbach)<unk>  describes the derivation of pH as a measure of acidity (using pKa, the acid dissociation constant) in biological and chemical systems. The<unk>  is also useful for estimating the pH of a buffer solution and finding the equilibrium pH in acid-base reactions (it is widely used to calculate isoelectric point of the proteins).
Henderson-Hasselbalch equation
Starling equation
Freundlich equation
Winters' formula
Gibbs free energy
Arrhenius equation
Langmuir equation
Bucherer-Bergs reaction