Question

19. (10pts) Which amino acid would give the following pH titration curve? 14.0 12.0 1001 8. 60 4.01 PNL O lequivalents) Draw the ionic specie(s) that exist at each of the following pH values? Keep in mind if the pHis very close to equilibrium pKa, show the two species of the equilibrium A) pH 1.0 B) pH 9.0 C) pH 2.0 | D) pH 10.76 E) pH 4.0

Answer 1

19. from the curve we know, LÞI = 10.8, pkai = 2,2, bka2 = 9,0, bkq3= 12.5 So, che amino acidis Arginine, (6) pH = | . HENV you :: NHL ONH3 ® pH = 9.0 NH2 : H . & H₂N HeNy Nitro :: ANHA ONH2 © PH= 2.0 NH3 HeNy OM - OHH . NH2 6) PH = 10,6 Ho No No NHA ☺ pH = 14,0 NH2 H₂N- • NH