Cho 9,97 gam hỗn hợp X gồm alanin và lysin tác dụng với dung dịch

Đáp án A.

$$\begin{gathered} \begin{array}{l}{\text{NH}}_2\text{CH}\left({\text{CH}}_3\right)\text{COOH}+\text{NaOH}\to {\text{NH}}_2\text{CH}\left({\text{CH}}_3\right)\text{COONa}+{\text{H}}_2\text{O}\\ xx\end{array} \\ \begin{array}{l}{\text{NH}}_2{\left[{\text{CH}}_2\right]}_4\text{CH}\left({\text{NH}}_2\right)\text{COOH}+\text{NaOH}\to {\text{NH}}_2{\left[{\text{CH}}_2\right]}_4\text{CH}\left({\text{NH}}_2\right)\text{COONa}+{\text{H}}_2\text{O}\\ \text{ \hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}y\hspace{0.17em} \hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}y}\end{array} \\ \begin{array}{l}{\text{NH}}_2\text{CH}\left({\text{CH}}_3\right)\text{COOH}+\text{HCl}\to {\text{ClNH}}_3\text{CH}\left({\text{CH}}_3\right)\text{COOH}\\ x x\end{array} \\ \begin{array}{l}{\text{NH}}_2{\left[{\text{CH}}_2\right]}_4\text{CH}\left({\text{NH}}_2\right)\text{COOH}+2\text{HCl}\to {\text{ClNH}}_3{\left[{\text{CH}}_2\right]}_4\text{CH}\left({\text{NH}}_3\text{Cl}\right)\text{COOH}\\ y 2y\end{array} \end{gathered}$$

Ta có hệ phương trình:

 $$\begin{gathered} \left\{\begin{array}{l}89x+146y=9,97\\ 111x+168y=11,73\end{array}\to \left\{\begin{array}{l}x=0,03\\ y=0,05\end{array}\right.\right. \\ {n}_{\text{HCl}}=n_{\text{alanin }}+2n_{\text{lysin }}=0,13 \text{\hspace{0.17em}\hspace{0.17em}mol} \end{gathered}$$

$\text{BTKL}:m_{muoái}=m_{\text{aminoaxit }}+m_{\text{HCl}}=9,97+0,13.36,5=14,715$ gam