The oxide that gives H2O2 most readily on treatment with H2O with out evaporation is :

(1) PbO2 + 2H2O → Pb(OH)4(2) Na2O2 + 2H2O → 2NaOH + H2O2this reaction is possible at room temperature(3) SnO2 + 2H2O → Sn(OH)4(4) Acidified BaO2 . 8H2O gives H2O2 after evaporation.