1)CH3-CH3=(t) CH2=CH2+H2
2)CH2=CH2+HOH=(H2SO4к) CH3-CH2-OH
3)CH3-CH2-OH+CuO=CH3COH+Cu+H2O
4)CH3COH+Cu(OH)2=CH3COOH+CuO+H2O
5)CH3COOH+CH3-CH2-OH=CH3COO-C2H5 + H2O
2Ba + O2 -> 2BaO
BaO + H2O -> Ba(OH)2
Ba(OH)2 + H2SO4 -> BaSO4 + 2H2O
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А=1
В=3
CH3Br + Br2 = CH2Br2 +HBr
Вроде бы так должно получиться