CHEM 120 Lecture Notes - Lecture 17: Titration, Cell Culture, Phenolphthalein

• School: McGill University
• Department: Chemistry
• Course: CHEM 120
• Professor: Laura Pavelka

Document Summary

17. 1 physical states and phase changes: strongest acid is superacid hsbf6, living organisms all depend upon ph, proteins (enzymes, motor muscles, nerves, skin) In protein, thousands of atoms, hundreds of ionizable groups: a- + h3o+ ah + h2o, at low ph, high [h3o+], weak acids and bases are pushed towards their protonated forms. Weak acids & bases: weak acids & bases are protonated at low ph, weak acid: [r-cooh] >> [r-coo-, weak base: [r-nh3. +] >> [r-nh2: weak acids & bases are deprotonated at high ph, weak acid [r-cooh] << [r-coo-, weak base: [r-nh3. [h3o+] can be altered by adding other acids and bases: common ion effect: bleach, e. coli leads to food poisoning. + h3o+ ph < 7 (dry ice, carbon dioxide bubbling up: bromthymol blue: pka = 7. 1 (yellow/acid to green to blue/basic) [ln-] (blue) / [hln] (yellow) = 10(ph pka) [ln-] = [hln] when ph = pka (in the middle, end point)