\(\left(1\right)2Na+2H_2O--->2NaOH+H_2\)
\(\left(2\right)2NaOH+H_2SO_4--->Na_2SO_4+2H_2O\)
\(\left(3\right)Na_2SO_4+BaCl_2--->BaSO_4\downarrow+2NaCl\)
\(\left(4\right)2NaCl+2H_2O\xrightarrow[có.màng.ngăn]{điện.phân}Cl_2+H_2+2NaOH\)
\(\left(5\right)2Fe+3Cl_2\overset{t^o}{--->}2FeCl_3\)