\(C_2H_4 + Br_2 \to C_2H_4Br_2\\ n_{C_2H_4} = n_{Br_2} = \dfrac{4}{160}=0,025(mol)\\ \%V_{C_2H_4} = \dfrac{0,025.22,4}{5,6}.100\% = 10\%\\ \%V_{CH_4}= 100\%-10\%=90\%\)
PTHH: \(C_2H_4+Br_2\rightarrow C_2H_4Br_2\)
Ta có: \(n_{Br_2}=\dfrac{4}{160}=0,025\left(mol\right)=n_{C_2H_4}\)
\(\Rightarrow\%V_{C_2H_4}=\dfrac{0,025\cdot22,4}{5,6}\cdot100\%=10\%\)
\(\Rightarrow\%V_{CH_4}=90\%\)