Verified answer

Ответ:

1) 2Ba + O2 = 2BaO

2) BaO + H2O = Ba(OH)2

3) Ba(OH)2  + 2HCl = BaCl2 + 2H2O

4) BaCl2 + 2BaOH = Ba(OH)2 + 2BaCl

5) Ba(OH)2 = BaO + H2O