Na + H2O => NaOH + 1/2H2
K2O + H2O => 2KOH
BaO + H2O => Ba(OH)2
N2O5 + H2O => 2HNO3
SO3 + H2O => H2SO4
P2O5 + 3H2O => 2H3PO4
K + H2O => KOH + 1/2H2
Ca + 2H2O => Ca(OH)2 + H2
CO2 + H2O <=> H2CO3
SO2 + H2O => H2SO3
CaO + H2O => Ca(OH)2
Na2O + H2O => 2NaOH