Ankadien liên hợp có CTPT dạng CnH2n−2 (n⩾4)
\(C_nH_{2n-2}+\left(1,5n-0,5\right)O_2\rightarrow nCO_2+\left(n-1\right)H_2O\)
\(\Rightarrow n_{C.trong.X}=n_{CO2}=\frac{11,2}{22,4}=0,5\left(mol\right)\)
\(\Rightarrow m_{H.trong.X}=6,8-m_{C.trong.X}=6,8-0,5.12=0,8\left(g\right)\)
\(n_{H.trong.X}=0,8\left(mol\right)\Rightarrow n_{H2O}=0,4\left(mol\right)\)
\(\Rightarrow n_X=n_{CO2}-n_{H2O}=0,5-0,4=0,1\left(mol\right)\)
\(\Rightarrow n=\frac{n_{CO2}}{n_X}=\frac{0,5}{0,1}=5\Rightarrow X:C_3H_8\)
X có các CTCT là:
CH2=CH−CH=CH−CH3; CH2=C(CH3)−CH=CH2