Hydrogen Peroxide 3 %: Barium Peroxide in Dilute Sulphuric Acid

Thénard first made hydrogen peroxide from barium peroxide; the improved way stirs the peroxide into sulphuric acid, which takes the barium out as insoluble barium sulphate. Titrate the clear liquid with permanganate to find its strength, dilute it to 3 %, the mild antiseptic and bleach, and keep it in a dark bottle. Even 3 % hurts the eyes. The picture: our diagram of the four stages.