Sulphuric acid, which has the traditional name, “oil of vitriol.” It is a nasty, corrosive liquid, making “vitriolic” an apt term for virulent language. At first it may seem odd that the term “vitriol” derives from the Latin meaning glass, since glass is an inert material. But there is a reasonable explanation. The earliest method of making sulphuric acid relied on heating naturally occurring minerals composed of sulphates. These compounds can exhibit quite different colors but they all have a decidedly “glassy” appearance. Copper sulphate is also known as blue vitriol, zinc sulphate as white vitriol, iron sulphate is green vitriol and cobalt sulphate is red vitriol. When heated, all these compounds convert to their oxide and give off water along with sulphur trioxide which then combine to form sulphuric acid. This process was supposedly discovered by the 8th century Muslim alchemist Jabir ibn Hayyan, known in English as Geber.
Vitriol became an extremely important in alchemy because it dissolved almost all substances except gold, which of course was the substance the alchemists were after. A classic example of what sulphuric acid can do is its reactivity with sugar. It almost instantly removes oxygen and hydrogen from the molecule leaving behind a mass of carbon which expands dramatically, inflated by the hot escaping gases. This reaction was cleverly used by MacGyver, the classic TV hero, who plugged up a leak in a sulphuric acid tank with a chocolate bar. Today, sulphuric acid is the most widely produced industrial chemical in the world, used in the production of fertilizer, steel and numerous plastics. Modern production relies on burning sulphur to form sulphur dioxide and reacting the latter with water. Sulphuric acid is a familiar chemical to most people, often appearing in popular culture. Everyone knows that Two Face, the villain in Batman was disfigured when sulphuric acid was thrown in his face. Interestingly it was once featured on an episode of Saturday Night Live in a sketch about “Sheriff Josh Acid,” who carried a flask of sulphuric acid instead of a gun. The episode was hosted by Mel Gibson who ironically when arrested for drunken driving made corrosive anti-semitic remarks and later apologized for the “vitriolic” language he had used.