Cho 200 ml dung dịch amino axit X nồng độ 0,4M tác...

B

- Hướng dẫn giải

\(\begin{gathered} + \,\,\left\{ \begin{gathered} {n_{ - COOH/X}} = {n_{NaOH}} = 0,08 \hfill \\ {n_X} = 0,08 \hfill \\ \end{gathered} \right. \Rightarrow \left\{ \begin{gathered} X\,\,la{}\,\,{({H_2}N)_n}RCOOH:0,08\,\,mol \hfill \\ muoi\,\,la{}\,\,{({H_2}N)_n}RCOONa:0,08\,\,mol \hfill \\ \end{gathered} \right. \hfill \\ \Rightarrow {M_{muoi}} = \frac{{10}}{{0,08}} = 125 \Rightarrow {M_X} = 125 - 22 = \boxed{103} \hfill \\ \end{gathered} \)