Mellitic anhydride, anhydride of mellitic acid

Mellitic acid

Mellitic acid, also called graphitic acid or benzenehexacarboxylic acid, is an acid first discovered in 1799 by M. H. Klaproth in the mineral mellite , which is the aluminium salt of the acid.- Preparation :...

, is organic compound

Organic compound

An organic compound is any member of a large class of gaseous, liquid, or solid chemical compounds whose molecules contain carbon. For historical reasons discussed below, a few types of carbon-containing compounds such as carbides, carbonates, simple oxides of carbon, and cyanides, as well as the...

 with formula C₁₂O₉.

Mellitic anhydride is oxide

Oxide

An oxide is a chemical compound that contains at least one oxygen atom in its chemical formula. Metal oxides typically contain an anion of oxygen in the oxidation state of −2....

 of carbon

Carbon

Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds...

  (oxocarbon

Oxocarbon

An oxocarbon or oxide of carbon is an inorganic compound consisting only of carbon and oxygen.The simplest and most common oxocarbons are carbon monoxide and carbon dioxide...

), like CO₂

Carbon dioxide

Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...

, CO

Carbon monoxide

Carbon monoxide , also called carbonous oxide, is a colorless, odorless, and tasteless gas that is slightly lighter than air. It is highly toxic to humans and animals in higher quantities, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal...

, and C₃O₂

Carbon suboxide

Carbon suboxide, or tricarbon dioxide, is an oxide of carbon with chemical formula C3O2 or O=C=C=C=O. Its four cumulative double bonds make it a cumulene...

. It is white sublimable solid, apparently obtained by Liebig and Wöhler

Friedrich Wöhler

Friedrich Wöhler was a German chemist, best known for his synthesis of urea, but also the first to isolate several chemical elements.-Biography:He was born in Eschersheim, which belonged to aau...

 in 1830 in their study of mellite

Mellite

Mellite, also called honeystone, is an unusual mineral being also an organic chemical. Chemically identified as an aluminium salt of mellitic acid; that is, aluminium benzene hexacarboxylate hydrate, with the chemical formula Al2C66·16H2O....

 ("honey stone"), who assigned it the formula C₄O_3. The substance was properly characterized in 1913 by H. Meyer and K. Steiner. It retains the aromatic character of the benzene ring.