\(n_{hh}=\frac{5,6}{22,4}=0,25\left(mol\right)\)
\(n_{C2H4Br2}=n_{Br2}=n_{C2H4}=\frac{18,8}{188}=0,1\left(mol\right)\)
\(V\%_{C2H4}=\frac{0,1}{0,25}.100\%=40\%\)
\(V\%_{CH4}=100\%-40\%=60\%\)
Đổi 200ml = 0,2l
\(\Rightarrow CM_{Br2}=\frac{0,1}{0,2}=0,5M\)