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CH4 →CH3Cl → CH3-CH3 → CH3CH2Br → C4H10
СРОЧНО!!!
1)СH4 + Cl2 = CH3Cl + HCl
2)2CH3Cl +2 Na = CH3- CH3 + 2NaCl
3)CH3 - CH3 + Br2 = CH3CH2Br + HBr
4)2CH3 - CH2Br + 2Na = CH3 - CH2 - CH2 - CH3 + 2NaBr