Why do the vast majority of compounds on earth contain carbon? This video looks at carbon's unique properties that give it its versatility with bonding and thus its enormous potential to create novel compounds both biologically and synthetically, as well as the shorthand of skeletal structures to show basic structures of complex molecules.
-More on organic chemistry | Wiki- Wikipedia 2 March 2019
In chemistry, an organic compound is generally any chemical compound that contains carbon. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. Study of the properties and synthesis of organic compounds is the discipline known as organic chemistry. For historical reasons, a few classes of carbon-containing compounds (e.g., carbonates and cyanides), along with a handful of other exceptions (e.g., carbon dioxide), are not classified as organic compounds and are considered inorganic. No consensus exists among chemists on precisely which carbon-containing compounds are excluded, making the definition of an organic compound elusive.[1] Although organic compounds make up only a small percentage of the Earth's crust, they are of central importance because all known life is based on organic compounds. Most synthetically produced organic compounds are ultimately derived from petrochemicals consisting mainly of hydrocarbons.
For many centuries, Western physicians and chemists believed in vitalism. This was the widespread conception that substances found in organic nature are created from the chemical elements by the action of a "vital force" or "life-force" (vis vitalis) that only living organisms possess. Vitalism taught that these "organic" compounds were fundamentally different from the "inorganic" compounds that could be obtained from the elements by chemical manipulations.
The organic compound L-isoleucine molecule presents some features typical of organic compounds: carbon-carbon bonds, carbon-hydrogen bonds, as well as covalent bonds from carbon to oxygen and to nitrogen.
As described in detail below, any definition of organic compound that uses simple, broadly applicable criteria turns out to be unsatisfactory, to varying degrees. The modern, commonly accepted definition of organic compound essentially amounts to any carbon containing compound, excluding several classes of substances traditionally considered as 'inorganic'. However, the list of substances so excluded varies from author to author. Still, it is generally agreed upon that there are (at least) a few carbon containing compounds that should not be considered organic. For instance, almost all authorities would require the exclusion of alloys that contain carbon, including steel (which contains cementite, Fe3C), as well as other metal and semimetal carbides (including "ionic" carbides, e.g, Al4C3 and CaC2 and "covalent" carbides, e.g. B4C and SiC, and graphite intercalation compounds, e.g. KC8). Other compounds and materials that are considered 'inorganic' by most authorities include: metal carbonates, simple oxides (CO, CO2, and arguably, C3O2), the allotropes of carbon, cyanide derivatives not containing an organic residue (e.g., KCN, (CN)2, BrCN, CNO−, etc.), and heavier analogs thereof (e.g., CP− 'cyaphide anion', CSe, COS; although CS2 'carbon disulfide' is often classed as an organic solvent). Halides of carbon without hydrogen (e.g., CF4 and CClF3), phosgene (COCl2), carboranes, metal carbonyls (e.g., nickel carbonyl), mellitic anhydride (C12O9), and other exotic oxocarbons are also considered inorganic by some authorities.
from Wikipedia March 2, 2019