(Solved): part ApartB  All amino acids have two ionizable functional groups: an \( \alpha \)-amino group ...

All amino acids have two ionizable functional groups: an \( \alpha \)-amino group (average \( \mathrm{p} K_{\mathrm{a}} \) of \( 9.4 \) ) and an \( \alpha \)-carboxylic acid group (average \( \mathrm{p} K_{\mathrm{a}} \) of 2.2). Aspartic acid has an ionizable side chain ( \( \mathrm{R} \) group) with a p \( K_{\mathrm{a}} \) of about \( 3.8 \). One of the possible ionization states of aspartic acid is shown in the image. At what \( \mathrm{pH} \) would the structure be the predominant ionization state? Consider the ionization state of all three of the functional amnine The protonated form of the \( \mathrm{R} \) group of aspartic acid is shown in the structure. The ratio of the protonated form to the charged (deprotonated) form depends on the \( \mathrm{p} K_{\mathrm{a}} \) of the \( \mathrm{R} \) group and the \( \mathrm{pH} \) of the solution. Select all the \( \mathrm{pH} \) values at which the charged form of the \( \mathrm{R} \) group would predominate. \( 2.2 \) \( 11.6 \) \( 3.8 \) \( 7.0 \)