CH4->CH3Cl->C2H6->C2H5OH->CH3COOH
1) CH4+Cl2=CH3Cl+HCl
2) 2CH3Cl+2Na=CH3-CH3+2NaCl
3) CH3-CH3+Cl2=CH3-CH2Cl+HCl
4) CH3-CH2Cl+NaOH=CH3-CH2OH+NaCl
5) CH3-CH2OH+{O}=CH3COOH
X-C2H5OH
