CHE 4341 Chapter Notes - Chapter 4: Alanine, Peptide, Amine
Document Summary
On r groups of asp, glu (=cooh) All will go from: ha+ to :a0 [all have n:"s!] On alpha carbon on all aa"s except one of them. * amide group of asn and gln side chains is not basic. > +1 charge: if ph > pka by 1 or more, then: weak basic form predominates (bc its present in 10:1 or more ratio) weak acid a- weak base a0. > 0 charge: if ph = pka > amount of weak acid = amount of weak base weak acid : overall charge = -0. 5 charge weak base : overall charge = +0. 5 charge. For weakly acidic groups: if ph is 1+ below pka > charge ~= 0 (on ha side) if ph is 1+ above pka > charge = -1 (on a- side) if ph = pka. > charge = -0. 5 (on both ha & a- side)
