Đáp án:
$CH_3-CH_2-CH-COOH\\\qquad\qquad \qquad\quad\Big|\\ \hspace{3.0cm}NH_2$
$\\ \qquad\quad CH_3\\\quad \quad\quad\,\,\,\Big|\\CH_3-C-COOH\\ \qquad \quad\,\,\,\Big|\\ \qquad \,\,\,\,NH_2$
Giải thích các bước giải:
X có dạng: $H_2NR(COOH)_a$
BTKL: $m_X+m_{HCl}=m_{\text{muối}}$
$\Rightarrow 10,3 + m_{HCl}=13,95\ \text{gam}\Rightarrow m_{HCl}=3,65\ \text{gam}$
$\Rightarrow n_{HCl}=\dfrac{3,65}{36,5}=0,1\ \text{mol}$
∝ aminoaxit X chứa 1 nhóm $NH_2$
$\Rightarrow n_X=n_{HCl}=0,1\ \text{mol}$
$\Rightarrow M_X=\dfrac{10,3}{0,1}=103\ \text{g/mol}$
$\Rightarrow M_R+45x=87$
$\Rightarrow \begin{cases}x=1\\ M_R=42\ (C_3H_6)\end{cases}$
$\Rightarrow$ CTCT thu gọn của X:
$CH_3-CH_2-CH-COOH\\\qquad\qquad \qquad\quad\Big|\\ \hspace{3.0cm}NH_2$
$\\ \qquad\quad CH_3\\\quad \quad\quad\,\,\,\Big|\\CH_3-C-COOH\\ \qquad \quad\,\,\,\Big|\\ \qquad \,\,\,\,NH_2$
