Cho các hợp chất: C2H6; C2H2; C2H4O2; C2H6O; C6H12O6.

Đáp án B

$\begin{array}{l}\%C_{\left(C_2{H}_6\right)}=\frac{12.2}{12.2+6}.100\%=80\%\\ \%C_{\left(C_2{H}_2\right)}=\frac{12.2}{12.2+2}.100\%=92,31\%\\ \%C_{\left(C_2{H}_4{O}_2\right)}=\frac{12.2}{12.2+4+16.2}.100\%=40\%\end{array}$

$\begin{array}{l}\%C_{\left(C_2{H}_{6}O\right)}=\frac{12.2}{12.2+6+16}.100\%=52,14\%\\ \%C_{\left(C_6{H}_{12}{O}_6\right)}=\frac{12.6}{12.6+12+16.6}.100\%=40\%\end{array}$