Đáp án đúng: B
Giải chi tiết:\(\begin{gathered} \begin{array}{*{20}{l}} {2{C_2}{H_5}OH\xrightarrow{{{H_2}S{O_4}dac,{{140}^o}C}}{C_2}{H_5}O{C_2}{H_5} + {H_2}O\;\;} \\ {\;x\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,0,5x\,\,\,\,\,\,\,\,\,\,\,\,\,\,0,5{\text{ }}x} \end{array} \hfill \\ \begin{array}{*{20}{l}} {{C_2}{H_5}OH\xrightarrow{{{H_2}S{O_4}dac,{{170}^o}C}}{C_2}{H_4} + {H_2}O\;\;\;} \\ \begin{gathered} y\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,y\,\,\,\,\,\,\,\,\,\,\,\,\,y \hfill \\ \begin{array}{*{20}{l}} {\;{H_2}O \to \frac{1}{2}{H_2}} \\ {\;0,75 \to 0,375} \end{array} \hfill \\ \end{gathered} \end{array} \hfill \\ \end{gathered} \)
nete/nanken = 0,5.0,5 : 0,5 = 1/2
Chọn B
