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

Solution

Chemistry ma’am · 2 steps

First check which oxides are true peroxides, then ask which one water alone can break apart.

1. Need a peroxide. H₂O₂ forms only when the solid already contains the peroxide ion O₂²⁻ (an O-O bond). Hydrolysis just adds H⁺ to that ion.

   Oxide	Metal oxidation state	Has O₂²⁻?	With water
   PbO₂	+4	No, it has two O²⁻	no H₂O₂
   Na₂O₂	+1	Yes	hydrolysed by cold water to give H₂O₂
   SnO₂	+4	No, it has two O²⁻	no H₂O₂
   BaO₂.8H₂O	+2	Yes	sparingly soluble, so it needs dilute H₂SO₄

   Na₂O₂ + 2H₂O →(ice-cold) 2NaOH + H₂O₂

2. So. Na₂O₂, option (b), gives H₂O₂ most readily on treatment with water.

The idea to keep. To get H₂O₂, the oxide must already hold an O-O bond, so check the oxidation state first. Na₂O₂ hydrolyses in cold water, but BaO₂ needs an acid.

Answer from the NTA final answer key. Solution by PrepWiser.