Question

Alanine forms Zwitter ion which exists as

• A. $C{H}_3\stackrel{\stackrel{\oplus {\text{NH}}_3}{|}}{C}HCO{O}^{-}$ in acidic medium
• B. $C{H}_3\stackrel{\stackrel{\oplus {\text{NH}}_3}{|}}{C}HCOOH$ in a medium of $pH=4$
• C. $C{H}_3\underset{\underset{{\text{NH}}_2}{|}}{C}HCO{O}^{-}$ in a medium of $pH=1$
• D. $C{H}_3\underset{\underset{{\text{NH}}_2}{|}}{C}HCO{O}^{-}$ in a medium of $pH=2$

Answer 1

The correct option is B $C{H}_3\stackrel{\stackrel{\oplus {\text{NH}}_3}{|}}{C}HCOOH$ in a medium of $pH=4$

$C{H}_3\underset{\underset{N{H}_2}{|}}{C}HCOOH\stackrel{H^{+}}{\to }C{H}_3\underset{\underset{\oplus N{H}_3}{|}}{C}HCOOH\underset{acidic}{\stackrel{H^{+}}{}}\underset{\text{Zwitter ion}}{C{H}_3\underset{\underset{\oplus N{H}_3}{|}}{C}HCO{O}^{-}}$
Zwitter ion is formed in the acidic medium as shown in the above reaction.