Properties:

Crystalline substance – white powder or transparent crystal, practically insoluble in water (solubility 0.0015 g/l at 18 °C and other solvents. Found in nature as mineral barite, which is the main barium ore.

Refractive index of a colloidal particle (dispersed phase).

Chemical properties:

• Barium sulfate is insoluble in alkalis and most acids, but soluble in chlorine water,hydrobromide And hydroiodide acids, solutions of alkali metal bicarbonates.
• Interacts with concentrated sulfuric acid, which converts insoluble sulfate into highly soluble barium hydrogen sulfate: BaSO4+H2SO4⟶Ba(HSO4)2

• When calcined with coal or coke sulfate is reduced to sulfide: BaSO4+4C⟶BaS+4CO↑

• At temperatures above 1600 °C it decomposes: 2BaSO4⟶2BaO+2SO2↑+O2↑

Toxicity:

Barium sulfate, due to its low solubility in water, is not a substance toxic to the body, unlike all soluble barium salts, and therefore it can be used as radiopaque substances. However, it is worth considering that it is used in medicine pharmacopoeial barium sulfate, which is guaranteed to be free of toxic impurities and infectious agents. Industrial barium sulfate may contain impurities that are toxic to humans.

Application:

Analytical chemistry:

IN analytical chemistry Barium sulfate is used as a good gravimetric form for the determination of sulfate ions and barium ions in gravimetric analysis.

X-ray contrast agent:

Often used for x-ray research gastro intestinal tract, since heavy barium atoms absorb well x-ray radiation. Although all soluble barium salts are poisonous, barium sulfate is practically insoluble in water (and in hydrochloric acid, which is contained in gastric juice), so it is non-toxic. For X-ray examination of the digestive organs, the patient takes orally suspension barium sulfate (“barite porridge”) with a barium content of 58.7% (mass fraction of barium in BaSO4).

Filler pigment:

Barium sulfate is one of the constituents of mixtures used as white pigments.

It is used as an adhesive paint, as it is insoluble in organic solvents. These whites are cheaper lead, unlike them, are not toxic and do not darken from hydrogen sulfide.

Other Applications:

Barium sulfate is used for various industrial purposes:

As a filler for photo- and writing paper, for linoleum and for some paints and varnishes. See, for example,baritage.

1. Like white filler For plastics.
2. In photometry: for coloring photometric spheres.
3. In the electrochemical industry during production lead acid batteries as an expander of the active mass of the negative electrode.
4. In the production of paste for glass etching.
5. During the production of some fireproof materials.
6. Protector for X-ray radiation (barium plaster for X-ray rooms).
7. Adding to Products Lego to provide radiopacity in case a child swallowed the part (this was an experiment that ended unsuccessfully in 1996, due to reduced strength of the parts and the toxicity of industrial grade barium sulfate).
8. As main component Zimmerit— armor coatings for German tanks and self-propelled guns from the Second World War.
9. As barite concentrate when drilling wells to weight clayey drilling fluids.
10. As a white pigment in paper production.