(i)It can be prepared by acidification of barium peroxide which is done by adding H₂SO₄. The excess water molecules then produced are evaporated under reduced pressure. The reaction for which is as follows-

BaO.8H₂O (s) + H₂SO₄ (aq) → BaSO₄(s) + H₂O₂ (aq) + 8H₂O (l)

H₂O₂ acts as an oxidizing as well as reducing agent in both acidic and alkaline medium. This can be illustrated by following examples-

A. Oxidizing action in acidic medium-

2Fe²⁺ + 2H⁺ + H₂O₂ → 2Fe³⁺ + 2H₂O

B. reducing agent in acidic medium-

2MnO₄^- + 6H⁺ + 5H₂O₂ → 2Mn²⁺ + 8H₂O + 5O₂

C. oxidizing agent in basic medium-

2Fe²⁺ + H₂O₂ → 2Fe³⁺ + 2OH^-

D. reducing agent in basic medium-

I₂ + H₂O₂ + OH^-→ 2I^- +2H₂O + O₂

(ii) Acidic property of Hydrogen peroxide-

It turns blue litmus red but its dilute solution is almost neutral to litmus which means it is a weak acid.

Its acidic nature can be further supported by its reaction with NaOH (base).

NaOH + H₂O₂ → NaHO₂ + 2H₂O

Since, H₂O₂ is a weak acid therefore CO₂ is not produced as final product.