# What does 'organic/non-organic molecule' means exactly? [duplicate]

I am new to the organic chemistry world. I was delving for the exact answer to my question, and I've found some results:

• In wikipedia (french), is was mentioned that an organic molecule contains Hydrogen, so that $\ce{CO2}$ is a non-organic molecule, but wait, what about $\ce{H2O}$? It's almost said a non-organic molecule and it does contain Hydrogen.

• And on other websites, I've read that an organic molecule is supposed to have 'Carbon' in its components, else, it will be called 'a non-organic molecule', the result that is an obvious contradictory to the first one.

What I've deducted from all my results is, that the organic molecule must contain Hydrogen or Carbon, and I'm not pretty sure of my deduction.

## marked as duplicate by ringo, Jan, Todd Minehardt, orthocresol♦, WildcatOct 6 '16 at 21:55

• Long story short, organic molecules are those which for historical reasons are studied in the department of organics. – Ivan Neretin Oct 6 '16 at 16:12

There are many different answers to the question, "What is an organic compound". Here are a few examples:

• Pudue - "compounds that contain both carbon and hydrogen"
• Britanica - compounds in which one or more atoms of carbon are covalently linked to atoms of other elements, most commonly hydrogen, oxygen, or nitrogen. The few carbon-containing compounds not classified as organic include carbides, carbonates, and cyanides
• Wikipedia - 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 (such as CO and CO2), and cyanides are considered inorganic
• UC Davis- Any compound containing carbon atom(s) is classified as an organic compound

Trying to pull the best from each of these while still keeping it simple, perhaps a good definition of an organic compound would be - any covalent compound containing, at least, carbon and hydrogen. Everything else would be inorganic.

For organic compounds, I like the "carbon skeleton" definition. There is some base carbon structure (linear, branched, cyclic) that we attach other structures to (functional groups). Hydrogens I think of as the "endcaps" of organic chemistry: if there is no interesting functional group to attach, you default to a hydrogen. This definition emphasizes the fact that chains of carbons (the skeleton) don't seem to have limits as to size. But we can also have very small carbon skeletons (e.g. $\ce{CH_4}$). So this is how I think about organic molecules.

• So what would CsCO3 be by your definition? – ron Jul 11 '14 at 3:00
• Typo, should be CaCO3 – ron Jul 11 '14 at 3:18
• I think it is a good idea to focus on the carbon skeleton (i.e. the C-C bond) instead of C-H, though obviously it makes necessary to define methane, methanol, carbonate, all carbides, if they belong or not to the organic matter. – Greg Jul 11 '14 at 8:08
• @ron: an ionic compound? ;-) Seriously, you're right that you would have to carefully go through various exceptions (e.g. carbonate ion not organic, but soaps are) if you wanted a comprehensive definition. I just wanted the skeleton idea out there. – user467 Jul 11 '14 at 10:54

Organic\non-organic molecules - is archaic term, which created in that time, when scientists thought, organics cannot be created in lab, only in living organism. Now, "Organic" mean "hydrocarbons", and "compound of hydrocarbons".