Осуществить следующие превращения CH3-CH2-CHCI2+KOH+H2O=X1+K2C2rO7+H2SO4=CH3-CH2-COOH+CI2=X2+NaHCO3=CH3-CHBr2

1) CH3-CH2-CHCI2 + 2KOH (водный р-р) = CH3-CH2-CHO (X1) + 2KCl + H2O;     2) 3CH3-CH2-CHO + K2C2rO7 + 4H2SO4 = 3CH3-CH2-COOH + K2SO4 + Cr2(SO4)3 + 4H2O;     3) CH3-CH2-COOH + Cl2 = CH3-CH(Cl)-COOH (X2) + HCl;     4) CH3-CH(Cl)-COOH + NaHCO3 = CH3-CH(Cl)-COONa + CO2 + H2O;     5) CH3-CH(Cl)-COONa + NaOH (+T) = CH3-CH2-Cl + Na2CO3;     6) CH3-CH2-Cl + NaOH = CH3-CH2-OH + NaCl;     7) CH3-CH2-OH + CuO (+T) = CH3-CHO + Cu + H2O;     8) CH3-CHO + PBr3 = CH3-CHBr2 + POBr.