Đốt cháy hoàn toàn m gam triglixerit X cần vừa đủ...

D

- Hướng dẫn giải

\(\begin{array}{l}
{{\rm{(RCOO)}}_{\rm{3}}}{\rm{C}}{}_{\rm{3}}^{}{{\rm{H}}_{\rm{5}}}{\rm{:x}}\,{\rm{mol}} \to \left\{ \begin{array}{l}
{\rm{C}}{{\rm{O}}_{\rm{2}}}{\rm{:}}\,{\rm{1,65}}\,{\rm{mol}}\\
{{\rm{H}}_{\rm{2}}}{\rm{O:}}\,{\rm{y}}\,{\rm{mol}}
\end{array} \right. \to {\rm{6x + 2,31}}{\rm{.2  =  1,65}}{\rm{.2}}\,{\rm{(1)}}\\
 \to {\rm{mX = mC + mH + mO  =  1,65}}{\rm{.12 + 2y + 6x}}{\rm{.16  =  96x + 2y + 19,8}}\\
{{\rm{(RCOO)}}_{\rm{3}}}{\rm{C}}{}_{\rm{3}}^{}{{\rm{H}}_{\rm{5}}}{\rm{:x}}\,{\rm{mol}} \to \left\{ \begin{array}{l}
{{\rm{C}}_{\rm{3}}}{{\rm{H}}_{\rm{5}}}{{\rm{(OH)}}_{\rm{3}}}{\rm{:x}}\,{\rm{mol}}\\
{\rm{RCOONa:}}\,{\rm{3x}}\,{\rm{mol}}
\end{array} \right.\\
 \to {\rm{96x  +  2y  +  19,8  +  40}}{\rm{.3x =  92}}{\rm{.3x  +  25,62}}\,{\rm{(2)}}\\
 \to \left\{ \begin{array}{l}
{\rm{x =  0,03}}\\
{\rm{y =  1,5}}
\end{array} \right. \to \left\{ \begin{array}{l}
\overline {\rm{C}} {\rm{ =  55}}\\
\overline {\rm{H}} {\rm{ =  100}}
\end{array} \right. \to {\rm{k =  6}}
\end{array}\)

Số π trong gốc hidrocacbon là 6 – 3 = 3 → a = 0,03.3 = 0,09 mol