Chlorine Atoms Cl

TABLE 6.14 Some Reported Values of the Rate Constants for the Reactions of Chlorine Atoms with Some Alkenes at 1 atm Total Pressure and 298 K 

The reaction proceeds primarily by addition to a double bond to form a chlorine-containing alkyl radical, which then adds 02 to ultimately generate characteristic chlorine-containing oxygenated products. For example, l-chloro-3-methyl-3-buten-2-one is formed in the absence of NO from the addition of chlorine atoms to the 4-position of isoprene, followed by secondary reactions of the alkyl radical with 02 etc. This product might therefore be expected to be a reaction product in the low-NOj. environment of the marine boundary layer (Nordmeyer et al., 1997). 

A small portion of the reaction proceeds by what appears to be abstraction of the allylic hydrogen atom from the weaker C-H bond (e.g., Lee and Rowland, 1977). In the case of the isoprene reaction, for example, about 15% of the overall reaction at 1 atm pressure and room temperature proceeds by abstraction (Ragains and Finlayson-Pitts, 1997). It should be noted, 

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An ionically bonded molecule (NaCl). (a) A sodium atom (Na) can donate the one electron in its valence shell to a chlorine atom (Cl), which has seven electrons in its outermost shell. The resulting ions (Na+ and CP) bond to form the compound sodium chloride (NaCl). The octet rule has been satisfied, (b) The ions that constitute NaCl form a regular crystalline structure in the solid state. 

On the other hand, an anion is an ion whose net charge is negative due to an increase in the number of electrons. A chlorine atom (Cl), for instance, can gain an electron to become the chloride ion Cl ... 

Four separate catalytic cycles have been discovered, all with catalyst X an add-electron species. X can be a chlorine atom (Cl), NO, OH, or H. The chain sequence with X = Cl is shown below... 

In this process, a chlorine atom (Cl) reacts with ozone (O3) to produce chlorine monoxide (CIO) and an oxygen molecule (O2). CIO can then combine with an oxygen atom (O) to reform Cl and O2. In this reaction set, because chlorine is reformed after destroying ozone, the cycle can repeat itself very quickly. 

Chlorinated hydrocarbons are chemicals made up of the elements carbon (C) and hydrogen (H) at the combine for the hydrocarbon part of the molecule, and chlorine atoms (Cl) substituted for hydrogen where a hydrogen atom was normally bonded to a carbon atom. Examples of structures of chlorinated hydrocarbons are given in Figure 1. 

Isotopic disorders (e.g. in solid chlorine atoms Cl and Cl isotopes can arise) and nuclear spin degeneracy ortho and para hydrogen) are two rather less important factors which can also give rise to residual disorder in solids at 0 K. 

We will use the built-in optimizer to optimize the molecule in a stepwise fashion. As Momec3 does not yet automatically assign atom types, please remember to set the atom type for each added atom manually. The list of defined atom types for the current force field can be found in the project-molecule-forcefields section the comments appended to the atom type normally give an indication of the use of the atom type. Atom types for all atoms in the tutorial are present in the standard force field. For platinum, select PT2, for the aliphatic nitrogen atoms the NT atom type, for the aliphatic carbon atoms CT, for the hydrogen atom H, and for the chlorine atoms CL. 

This reaction proceeds by a chain mechanism involving a repetitive sequence of elementary reactions involving the three stable molecules listed in Eq. (1), as weU as two short-lived free radical intermediates, i.e., chlorine atoms (Cl) and hydrogen atoms (H). The most important... 

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