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In organic chemistry, a primary carbon is a carbon atom which is bound to only one other carbon atom. [1] It is thus at the end of a carbon chain . In case of an alkane , three hydrogen atoms are bound to a primary carbon (see propane in the figure on the right).
The α-carbon (alpha-carbon) refers to the first carbon atom that attaches to a functional group, such as a carbonyl. The second carbon atom is called the β-carbon ( beta -carbon), the third is the γ-carbon ( gamma -carbon), and the naming system continues in alphabetical order.
Archaeological materials, such as bone, organic residues, hair, or sea shells, can serve as substrates for isotopic analysis. Carbon, nitrogen and zinc isotope ratios are used to investigate the diets of past people; these isotopic systems can be used with others, such as strontium or oxygen, to answer questions about population movements and cultural interactions, such as trade.
Carbon is one of the few elements that can form long chains of its own atoms, a property called catenation.This coupled with the strength of the carbon–carbon bond gives rise to an enormous number of molecular forms, many of which are important structural elements of life, so carbon compounds have their own field of study: organic chemistry.
Carbon (6 C) has 14 known isotopes, from 8 C to 20 C as well as 22 C, of which 12 C and 13 C are stable. The longest-lived radioisotope is 14 C, with a half-life of 5.70(3) × 10 3 years. This is also the only carbon radioisotope found in nature, as trace quantities are formed cosmogenically by the reaction 14 N + n → 14 C + 1 H. The most ...
The following is a list of straight-chain alkanes, the total number of isomers of each (including branched chains), and their common names, sorted by number of carbon atoms. [ 1 ] [ 2 ] Number of C atoms
An increase in primary productivity causes a corresponding rise in δ 13 C values as more 12 C is locked up in plants. This signal is also a function of the amount of carbon burial; when organic carbon is buried, more 12 C is locked out of the system in sediments than the background ratio.
13 C NMR spectroscopy is much less sensitive (ca. by 4 orders of magnitude) to carbon than 1 H NMR spectroscopy is to hydrogen, because of the lower abundance (1.1%) of 13 C compared to 1 H (>99%), and because of a lower(0.702 vs. 2.8) nuclear magnetic moment.