SULFURIC ACID 37%, 50%, 94–97%

Sulfuric acid (H [14]2S [15]O [16]4) is a colorless, high-density liquid, a strong diprotic mineral acid [17]. It mixes with water [18] without limitation. Sulfuric acid is one of the most important compounds [19] in the chemical industry [20] and the substance produced in the largest quantities. In 2001 [21], 165 million tons were produced. The fertilizer industry [22] uses it in the largest proportion, but almost every sector of the chemical industry [23] employs it as a basic raw material.

Concentrated sulfuric acid is a powerful dehydrating agent. Although 100% concentration, so-called _fuming sulfuric acid_ (also known as _oleum_ [24]) can be produced, in practice, acids stronger than 98.3% are not used due to the evaporation of sulfur trioxide [25] (SO3).