`a)`

`(1)CH_3CHO+1/2O_2` $\xrightarrow{t^o,xt}$ `CH_3COOH`

`(2)CH_3COOH+NaOH->CH_3COONa+H_2O`

`(3)CH_3COONa+HCl->CH_3COOH+NaCl`

`(4)CH_3COOH+C_2H_5OH` $\buildrel{{t^o,H^+}}\over\rightleftharpoons$ `CH_3COOC_2H_5+H_2O`

`b)`

`(1)C_2H_4+H_2O` $\xrightarrow{t^o,H^+}$ `C_2H_5OH`

`(2)C_2H_5OH+CuO` $\xrightarrow{t^o}$ `CH_3CHO+Cu+H_2O`

`(3)CH_3CHO+1/2O_2` $\xrightarrow{t^o,xt}$ `CH_3COOH`

`(4)CH_3COOH+CH_3OH` $\buildrel{{t^o,H^+}}\over\rightleftharpoons$ `CH_3COOCH_3+H_2O`

`c)`

`(1)C_2H_4+H_2O` $\xrightarrow{t^o,H^+}$ `C_2H_5OH`

`(2)C_2H_5OH+O_2` $\xrightarrow{men\ giấm}$ `CH_3COOH+H_2O`

`(3)CH_3COOH+KOH->CH_3COOK+H_2O`

`(4)CH_3COOK+HCl->CH_3COOH+KCl`

`d)`

`(1)C_6H_{12}O_6` $\xrightarrow{enzyme}$ `2C_2H_5OH+2CO_2`

`(2)C_2H_5OH+CuO` $\xrightarrow{t^o}$ `CH_3CHO+Cu+H_2O`

`(3)CH_3CHO+H_2` $\xrightarrow{t^o,Ni}$ `C_2H_5OH`

`(4)CH_3COOH+C_2H_5OH` $\buildrel{{t^o,H^+}}\over\rightleftharpoons$ `CH_3COOC_2H_5+H_2O`