Question

H2C2O4-->CO-->X1-->над стрелкой(CH3COOH)X2-->над стрелкойNaOH+H2O,t X3-->CH4

Answer 1

1.Н2С2О4=Н2O+CO+CO2
2.CO+2H2=CH3OH -x1
3.CH3OH+CH3COOH⇔CH3COOCH3 +H2O
4.CH3COOCH3 +NaOH⇒CH3COONa (x2)+CH3OH 
5.CH3COONa+NaOH(x3)⇒Na2CO3+CH4↑