Question

(10) (2) © © eg 2. Consider the amino acid, glycine, in its fully protonated form *H3NCH2CO2H, where the pka1 = 2.35 and pka2 = 9.78. a) Kaz is the equilibrium constant for the second dissociation of *H3NCH2CO2H. Write the chemical equation that illustrates this equilibrium. b) Write the structure for the major species at pH = 1.35. c) Write the structure for the major species at pH = 3.35. d) Write the structure for the major species at pH = 10.78. e) Calculate the isoelectric point, pl. f) What is the name of the technique that could be used to separate the different structures of glycine.

Answer 1

l0 Pka2.35 pla,9.78 CHNRt CH2NH2 H Coo Coo lyan ill have b) At pHl35 most fretoraad form CH-NHt 4 fetoaled \ CooH ' Pha 2.35

c) At pH 335 re oton has dissocidt pka 2.35 + CR-NMS ) At pH- lo-3, both Poutons have boen dissociake CH-NH CoD e) PI pkat plaz = + 2.35t4.78 2 I-6.065 isoclectsic font Electrethoresia is the technugu to sfarate differedk whch is used vamino auids 4t olepands on trovement echarges Ahuchoe nder the tnfluunce elecbui field