Make up the reaction equation: Fe- FeCl2- Fe (OH) 2- FeSo4- BaSo4

1) Fe + 2HCl = FeCl2 + H2 (when iron interacts with hydrogen chloride, ferric chloride and hydrogen are formed);

2) FeCl2 + 2NaOH = Fe (OH) 2 + 2NaCl (when iron chloride interacts with sodium hydroxide, iron hydroxide and sodium chloride are formed);

3) Fe (OH) 2 + H2SO4 = FeSO4 + 2H2O (when iron hydroxide interacts with sulfuric acid, iron sulfate and water are formed);

4) FeSO4 + BaCl2 = BaSO4 + FeCl2 (when ferrous sulfate interacts with barium chloride, barium sulfate and ferric chloride are formed).