Pure is dangerously unstable and undergoes auto-oxidation (disproportionation) into water and oxygen — Hydrogen Chemistry Question

💡 Solution & Explanation

$H_2O_2$ decomposes rapidly upon exposure to light, rough surfaces, dust, trace heavy metals, and importantly, alkali oxides found in ordinary glass. Therefore, it is stored in dark, wax-lined or Teflon bottles. Stabilizers like urea, acetanilide, or phosphoric acid are added to retard decomposition.