CHEM 153A Lecture Notes - Lecture 1: Titration Curve, Stage Name, Acid Dissociation Constant
Document Summary
Measure of the strength of acid or base character of a substance. Ph of the solution where [ha] = [a-] (half-equivalence point) Predict the protonation state and charge of a functional group given pka and ph data. Explain how a buffer works, and why it is important for biological systems. Change in ph affects the protonation state of aa which can alter protein structure & function. Solutions that contains a weak acid (ha) & its conjugate base (a-) that resists changes in ph upon the addition of strong acid/base. Good buffers only within 1 unit of the pka (ratio of a-:ha is 10:1 showing there"s only 10% of weak acid present) further away, not enough weak acid to resist the ph change. Polyprotic acids have more than one pka thus having more than 1 half-equivalence points & buffering regions. Know the full name, 3 letter code, one letter code, & structure for all 20 standard amino acids.
