Barium hydroxide is used in analytical chemistry for the titration of weak acids, particularly organic acids. Its clear aqueous solution is guaranteed to be free of carbonate, unlike those of sodium hydroxide and potassium hydroxide, as barium carbonate is insoluble in water. This allows the use of indicators such as phenolphthalein or thymolphthalein (with alkaline colour changes) without the risk of titration errors due to the presence of carbonate ions, which are much less basic.

Barium peroxide is the inorganic compound with the formula BaO2. This white solid (gray when impure) is one of the most common inorganic peroxides, and it was the first peroxide compound discovered. Being an oxidizer and giving a vivid green color upon ignition (as do all barium compounds), it finds some use in fireworks and hair dyes; historically, it was also used as a precursor for hydrogen peroxide.

Sodium Sulphide (Iron Free)

Sodium Sulphide Flakes Iron Free. Sodium sulfide is the chemical compound with the formula Na2S and it has an antfluorite structure. It's a yellow appearance, water-soluble salts that give strongly alkaline solutions. When exposed to moist air, Na2S emit hydrogen sulfide, which smells like rotten eggs.