The first and faster process is the removal of hydrogen and oxygen as units of water by the concentrated sulfuric acid. This occurs because hydration of concentrated sulfuric acid is strongly thermodynamically favorable, with a standard enthalpy of reaction (ΔH) of −880 kJ/mol. It is this rapid dehydrating reaction, rather than its acidity itself, that makes concentrated sulfuric acid, and so piranha solution, dangerous to handle. This dehydration process exhibits itself as the rapid carbonisation of common organic materials, especially carbohydrates, when they enter in contact with a piranha solution. Piranha solution was named in part for the vigor of this first process, since large quantities of organic residues immersed in the solution are dehydrated so violently that the process resembles a piranha feeding frenzy. The second and more definitive rationale for the name, however, is the ability of piranha solution to "eat anything", in particular, elemental carbon in the form of soot or char. This second and far more interesting process can be understood as the sulfuric-acid boosted conversion of hydrogen peroxide from a relatively mild oxidizing agent into one sufficiently aggressive to dissolve elemental carbon, a material that is notoriously resistant to room-temperature aqueous reactions (as, e.g., with sulfochromic acid). This transformation can be viewed as the energetically favorable dehydration of hydrogen peroxide by concentrated sulfuric acid to form hydronium ions, bisulfate ions, and, transiently, atomic oxygen radicals (very labile ): It is this extremely reactive atomic oxygen species that allows piranha solution to dissolve elemental carbon. Carbon allotropes are difficult to attack chemically because of the highly stable and typically graphite-like hybridized bonds that surface carbon atoms tend to form with each other. The most likely route by which the solution disrupts these stable carbon–carbon surface bonds is for an atomic oxygen first to attach directly to a surface carbon to form a carbonyl group: In the above process, the oxygen atom in effect "steals" an electron bonding pair from the central carbon, forming the carbonyl group and simultaneously disrupting the bonds of the target carbon atom with one or more of its neighbours. The result is a cascading effect in which a single atomic oxygen reaction initiates significant "unraveling" of the local bonding structure, which in turn allows a wide range of aqueous reactions to affect previously "impervious" carbon atoms. Further oxidation, for example, can convert the initial carbonyl group into carbon dioxide and create a