a/

$Al+3/2O_2 \buildrel{{t^o}}\over\longrightarrow Al_2O_3$

$Al_2O_3+6HCl \to 2AlCl_3+3H_2O$

$AlCl_3+3NaOH \to Al(OH)_3+3NaCl$

$2Al(OH)_3 \buildrel{{t^o}}\over\longrightarrow  Al_2O_3+3H_2O$

$Al_2O_3+2NaOH \to 2NaAlO_2+H_2O$

b/

$Fe(OH)_2  \buildrel{{t^o}}\over\longrightarrow  FeO+H_2O$

$FeO+2HCl \to FeCl_2+H_2O$

$FeCl_2+Mg \to Fe+MgCl_2$

$Fe+3/2Cl_2 \buildrel{{t^o}}\over\longrightarrow  FeCl_3$

$FeCl_3+3NaOH \to Fe(OH)_3+3NaCl$

c/

$Al_4C_3+12H_2O \to 3CH_4+4Al(OH)_3$

$2CH_4 \buildrel{{1500^oC, \text{làm lạnh nhanh}}}\over\longrightarrow  C_2H_2+3H_2$

$C_2H_2+H_2  \buildrel{{t^o,Pb/PbCO3}}\over\longrightarrow C_2H_4$

$C_2H_4+H_2O \buildrel{{H^+,t^o}}\over\longrightarrow CH_3-CH_2-OH$

$CH_3-CH_2-OH +CuO \buildrel{{t^o}}\over\longrightarrow CH_3CHO+Cu+H_2O$

d/

$(C_6H_{10}O_5)_n+nH_2O \buildrel{{xt}}\over\longrightarrow nC_6H_{12}O_6$

$C_6H_{12}O_6 \buildrel{{\text{lên men}}}\over\longrightarrow 2C_2H_5OH+2CO_2$

$CH_3-CH_2-OH+CuO \buildrel{{t^o}}\over\longrightarrow CH_3CHO+Cu+H_2O$

$CH_3CHO+Br_2+H_2O \to CH_3COOH+2HBr$

$CH_3COOH+Na \to CH_3COONa+1/2H_2$