∞ generated and posted on 2016.12.18 ∞
Molecules or ions containing carbon atoms that are covalently bonded to one or more hydrogen or carbon atoms, or other atoms, but other than with all carbon atoms solely bonded to oxygen or nitrogen atoms.
Non-organic forms are carbon include especially carbon dioxide (0=C=0, or CO2) but also carbon monoxide (CO, with a triple bond between the carbon and the oxygen). For a more complete list as well as history, see organic compound. By contrast, see instead organic food along with related subjects reachable via this Wikipedia disambiguation link.
Figure legend: Simplest of organic compounds, methane. Note the four single bonds between a single carbonatom and four different hydrogen atoms. Note that not all of carbon's electrons are shown, but instead just the valence electrons. Hydrogen atoms, by contrast, possess just a single electron. The bonds shown are single covalent bonds. They are energy rich, and they also can be viewed as reduced in the sense of trapping electrons and therefore their associated energy some distance from the atomic nuclei with which they are associated.
The simplest of organic molecules contain a single carbon atom and include methane (CH4), methanol (CH3OH), formaldehyde (CH2O), and formic acid (CHOOH). In each of these cases carbon is found to at least one hydrogen atoms (and in fact in order the carbons are bound to 4, 3, 2, and 1 hydrogen atom(s), respectively). Carbonic acid, by contrast, also possesses two hydrogen atoms, but three oxygens and in fact is interconvertible with carbon dioxide in combination with water (as catalyzed by carbonic anhydrase as found in red blood cells).
The number of oxygen-to-carbon bonds in this progression is 0, 1, 2, 3, and 4, keeping in mind that formaldehyde and formic acid each have one carbon-to-oxygen double bond whereas in carbonic acid as cell as carbon dioxide there are two carbon-to-oxygen double bonds.
Note in these progression that the single carbon atom is becoming more oxidized, going from methane to CO2. Going from carbon dioxide to methane, by contrast, the single carbon atom is becomes increasingly reduced. These ideas in fact are helpful for understanding such catabolic reactions as glycolysis, pyruvate oxidation, and the Krebs citric acid cycle.