Technical sulfuric acid. Chemical symbol: H2SO4. It is one of the basic materials of the chemical industry. It is produced by the chamber and contact method. The raw materials for the production of sulfuric acid are: sulfur, piryt (FeS2 - iron disulfide) i anhydryt. Depending on the production method, a distinction is made: ventricular sulfuric acid, tower, contact, oleum i. regenerated. The domestic industry produces the following grades of sulfuric acid: a) technical chamber 60 Be, 76—78 ° / o, b) technical contact 66 Be, c) fuming oleum with the content of 20% free SO3, d) fuming oleum with the content of 25% free SO3, e) fuming oleum with the content of 65% free SO3. In addition, battery sulfuric acid is produced, featured separately, as the next article. Technical sulfuric acid is an oily fluid, transparent, colorless or yellowish brown to reddish brown, highly hygroscopic, easily destroys organic bodies. C. on. a) ventricular acid 1,72, you. 60°Be, b) contact acid 1,834, i.e.. 66°Be. In construction, sulfuric acid is used in electroplating of metal parts as a stain in metalworking (auxiliary production), for cleaning copper objects, brass, zinc and matting metal objects.