Phản ứng thế : $CH_4 , C_2H_6 , C_4H_{10} , C_3H_8 $
+ PTHH : $ CH_4 + Cl_2 \xrightarrow{\text{ánh sáng}} CH_3Cl + HCl \\ C_2H_6 + Cl_2 \xrightarrow{\text{ánh sáng}} C_2H_5Cl + HCl \\ C_4H_{10} + Cl_2 \xrightarrow{\text{ánh sáng}} C_4H_9Cl + HCl \\ C_3H_8 + Cl_2 \xrightarrow{\text{ánh sáng}} C_3H_7Cl + HCl $
Có dạng : $ C_nH_{2n +2 } + Cl_2 \xrightarrow{\text{ánh sáng }} C_nH_{2n+1}Cl + HCl $
Làm mất màu dd Brom : $ C_2H_4 , C_2H_2 $
+ PTHH : $ C_2H_2 + 2Br_2 \rightarrow C_2H_2Br_4 \\ C_2H_4 + Br_2 \rightarrow C_2H_4Br_2 $