a.
BaO + H2O → Ba(OH)2
K2O + H2O → 2KOH
Na2O + H2O → 2NaOH
SO2 + H2O → H2SO3
b.
Fe2O3 + 3H2 ----to----> 2Fe + 3H2O
CuO + H2 ----to---> Cu + H2O
ZnO + H2 ----to----> Zn + H2O
a) BaO + H2O → Ba(OH)2
K2O + H2O → 2KOH
Na2O + H2O → 2NaOH
SO2 + H2O → H2SO3
b) Fe2O3 + 3H2 ----to----> 2Fe + 3H2O
CuO + H2 ----to---> Cu + H2O
ZnO + H2 ----to----> Zn + H2O