1) в две стадии: а) СО+ NaOH=HCOONa b) 2HCOONa+H2SO4=2HCOOH+Na2SO4

2) CaC2 + H2O --> Ca(OH)2 + H2C2 
H2C2 + H2O -(HgSO4)-> CH3-CH=O(ацетальдегид) 
CH3-CH=O + [O] --> CH3-COOH

3) C2H4+HCl=C2H5Cl

      C2H5Cl+CH3-Mg-Cl=C2H5-CH3+MgCl2

      C3H8(t,Ni)=C3H6+H2

      CH2=CH-CH3+CO+H2(t,k)= CH3-CH2-CH2-COH

1)CO+H2 (t,k) =H-COH

    H-COH+Ag2O (t) =H-COOH+2Ag

2)CaC2+2HOH=Ca(OH)2+C2H2

    C2H2+HOH (t,Hg2+) = CH3-COH

    CH3-COH+Ag2O(t) =CH3-COOH+2Ag

3)C2H4+HCl=C2H5Cl

      C2H5Cl+CH3-Mg-Cl=C2H5-CH3+MgCl2

      C3H8(t,Ni)=C3H6+H2

      CH2=CH-CH3+CO+H2(t,k)= CH3-CH2-CH2-COH-оксосинтез