Ответ:

Объяснение:

4Na + O2 = 2Na2O

Na2O + H2O = 2NaOH

2NaOH + H2SO4 = Na2SO4 + 2H2O

Na2SO4 + BaCl2 = BaSO4 + 2NaCl

2Ca + O2 = 2CaO

CaO + H2O = Ca(OH)2

Ca(OH)2 + 2HCl = CaCL2 + 2H2O

CaCl2 -> Ca + Cl2