Bicine is an amino acid, but not a building block of proteins. Rather, it is a reagent commonly used in the biochemistry laboratory. Bicine contains two ionizable groups: tertiary amine (pKa 8.3) and carboxyl (pKa 2.3)
a. For each of the ionizable groups in bicine, draw its HA and A- form.
b. How many molar equivalents of NaOH are required to titrate bicine completely?
c. In a titration of bicine, which group will be deprotonated first?
d. Draw the titration curve for bicine. Clearly label the axes, the pKas and the equivalence points.
e. At which pH range(s) does bicine act as a buffer?
f. On the titration curve clearly indicate the point at which the net charge of bicine is zero.
g. Is the structure of bicine shown above correct? If yes, explain why. If not, draw the correct structure with a net charge of zero.
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