Đáp án:
228 B
229 B
Giải thích các bước giải:
\(\begin{array}{l}
228)\\
{n_{{C_{17}}{H_{33}}COONa}} = \dfrac{{15,2}}{{304}} = 0,05\,mol\\
{n_{{C_{17}}{H_{35}}COONa}} = \dfrac{{30,6}}{{306}} = 0,1\,mol\\
{n_{{C_{17}}{H_{33}}COONa}}:{n_{{C_{17}}{H_{35}}COONa}} = 0,05:0,1 = 1:2\\
\Rightarrow \text{ Trong X có 1 gốc }\,{C_{17}}{H_{33}}COO\, \text{ và 2 gốc }\,{C_{17}}{H_{35}}COO\\
CT\,X:({C_{17}}{H_{33}}COO){({C_{17}}{H_{35}}COO)_2}{C_3}{H_5}\\
\Rightarrow {M_X} = 888\,g/mol\\
229)\\
{n_{KOH}} = \dfrac{{18,77 - 17,81}}{{39 - 23}} = 0,06\,mol\\
{n_{{C_3}{H_5}{{(OH)}_3}}} = \dfrac{{{n_{KOH}}}}{3} = 0,02\,mol\\
BTKL:\\
{m_X} + {m_{KOH}} = {m_{xp}} + {m_{{C_3}{H_5}{{(OH)}_3}}}\\
\Rightarrow {m_X} = 18,77 + 0,02 \times 92 - 0,06 \times 56 = 17,25g
\end{array}\)
