Search results
Results from the WOW.Com Content Network
A reaction coordinate diagram may also have one or more transient intermediates which are shown by high energy wells connected via a transition state peak. Any chemical structure that lasts longer than the time for typical bond vibrations (10 −13 – 10 −14 s) can be considered as intermediate. [4]
Carbon–carbon bond-forming reactions are organic reactions in which a new carbon–carbon bond is formed. They are important in the production of many human-made chemicals such as pharmaceuticals and plastics. The reverse reaction, where a carbon-carbon bond is broken, is known as carbon-carbon bond activation.
The chemical process practiced on the largest scale is the reaction of benzene and ethene to give ethylbenzene: C 6 H 6 + C 2 H 4 → C 6 H 5 CH 2 CH 3 The resulting ethylbenzene is dehydrogenated to styrene and then polymerized to manufacture polystyrene , a common thermoplastic material.
The bond energy for H 2 O is the average energy required to break each of the two O–H bonds in sequence: Although the two bonds are the equivalent in the original symmetric molecule, the bond-dissociation energy of an oxygen–hydrogen bond varies slightly depending on whether or not there is another hydrogen atom bonded to the oxygen atom.
The term bond-dissociation energy is similar to the related notion of bond-dissociation enthalpy (or bond enthalpy), which is sometimes used interchangeably.However, some authors make the distinction that the bond-dissociation energy (D 0) refers to the enthalpy change at 0 K, while the term bond-dissociation enthalpy is used for the enthalpy change at 298 K (unambiguously denoted DH° 298).
Ethane (US: / ˈ ɛ θ eɪ n / ETH-ayn, UK: / ˈ iː θ eɪ n / EE-thayn) is a naturally occurring organic chemical compound with chemical formula C 2 H 6. At standard temperature and pressure, ethane is a colorless, odorless gas. Like many hydrocarbons, ethane is isolated on an industrial scale from natural gas and as a petrochemical by ...
The aromatic products of the reaction are then separated from the reaction mixture (or reformate) by extraction with any one of a number of solvents, including diethylene glycol or sulfolane, and benzene is then separated from the other aromatics by distillation. The extraction step of aromatics from the reformate is designed to produce ...
Outside of the industrial sector, cracking of C−C and C−H bonds are rare chemical reactions. In principle, ethane can undergo homolysis: CH 3 CH 3 → 2 CH 3 ⋅. Because C−C bond energy is so high (377 kJ/mol), [18] this reaction is not observed under laboratory conditions. More common examples of cracking reactions involve retro-Diels ...