Gọi \(\left\{{}\begin{matrix}n_{C2H2}:a\left(mol\right)\\n_{C2H4}:b\left(mol\right)\end{matrix}\right.\)
\(\Rightarrow26a+28b=5,4\left(1\right)\)
\(n_{CO2}=0,4\left(mol\right)\)
\(\Rightarrow2a+2b=0,4\left(2\right)\)
\(\left(1\right)+\left(2\right)\Rightarrow\left\{{}\begin{matrix}a=0,1\left(mol\right)\\b=0,1\left(mol\right)\end{matrix}\right.\)
\(\Rightarrow\%V_{C2H2}=\%V_{C2H4}=\frac{0,1}{0,1+0,1}.100\%=50\%\)