Sulfuric acid is a clear, colourless to dark brown, odourless, dense, oily liquid. It will not burn but it can decompose at high temperatures forming toxic gases, such as sulfur oxides. Contact of sulfuric acid with combustible materials may cause fire. It is considered to be highly reactive. Contact with many organic and inorganic chemicals may cause fire or explosion and contact with metals liberates flammable hydrogen gas. It also reacts violently with water.

Sulfuric acid is VERY TOXIC. It may be fatal if inhaled or swallowed and it is CORROSIVE to the eyes, skin and respiratory tract. It may cause blindness and permanent scarring. It also causes lung injury and these effects may be delayed. Strong inorganic acid mists containing sulfuric acid are CARCINOGENIC.

The main use is in the manufacture of phosphate and ammonium sulfate fertilizers. Other important uses include production of rayon and other textile fibres, inorganic pigments, nitrate explosives, alcohols, plastics, dyes, drugs, synthetic detergents, natural and synthetic rubber, pulp and paper, cellulosics and catalysts. It is also used to make hydrochloric and hydrofluoric acids, aluminum and copper sulfate and chromium chemicals. It is used in petroleum refining, in pickling iron, steel and other metals, as a leaching agent for ores, in electroplating baths, as an alkylation catalyst, as a component of lead storage batteries and as a laboratory reagent.

Sulfuric acid is sold or used commercially in different concentrations, including technical (78 to 93%) and other grades (96, 98-99, and 100%). Impurities include metals such as iron, copper, zinc, arsenic, lead, mercury and selenium, sulfurous acid (as SO2), nitrates and chlorides.

Sulfuric acid is also known as battery acid, dihydrogen sulfate, electrolyte acid, hydrogen sulfate, mattling acid, oil of vitriol, spirit of sulfur, sulphuric acid, and acide sulfurique.

Its CAS Registry Number is 7664-93-9. This number is assigned by the Chemical Abstracts Service (CAS) in the United States and is used as a unique identifier number world-wide.