Methyl Chloride CH3CI

Methyl chloride supplies about 0.5 ppb of chlorine to the stratosphere. Prior to 1996, the atmospheric input of CH3CI was assumed to be a result of biological processes in the ocean. Tropical terrestrial sources, biomass burning and tropical plants, are now believed to be important. The dominant sink of CH3CI is reaction with the OH radical in the 

TABLE 2.16 Global Budget of Methyl Chloride (CH3C1) 

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Naturally occurring isotopes of any element are present in unequal amounts. For example, chlorine exists in two isotopic forms, one with 17 protons and 18 neutrons ( Cl) and the other with 17 protons and 20 neutrons ( Cl). The isotopes are not radioactive, and they occur, respectively, in a ratio of nearly 3 1. In a mass spectrum, any compound containing one chlorine atom will have two different molecular masses (m/z values). For example, methyl chloride (CH3CI) has masses of 15 (for the CH3) plus 35 (total = 50) for one isotope of chlorine and 15 plus 37 (total = 52) for the other isotope. Since the isotopes occur in the ratio of 3 1, molecular ions of methyl chloride will show two molecular-mass peaks at m/z values of 50 and 52, with the heights of the peaks in the ratio of 3 1 (Figure 46.4). 

Bonds may also be broken symmetrically such that each atom retains one electron of the pair that formed the covalent bond. This odd electron is not paired like all the other electrons of the atom, i.e. it does not have a partner of opposite spin. Atoms possessing odd unpaired electrons are termed free radicals and are indicated by a dot alongside the atomic or molecular structure. The chlorination of methane (see later) to produce methyl chloride (CH3CI) is a typical free-radical reaction ... 

Figure 6. Measured molecular structure of methyl chloride (CH3CI), taken from Jensen (1981). CH3CI is a nearly tetrahedral molecule with symmetry. All C-H bond lengths, H-C-H angles and H-C-Cl angles are identical.

Alkyl halides (haloalkanes) are a class of compounds where a halogen atom or atoms are attached to a tetrahedral carbon sp ) atom. The functional group is —X, where —X may be —F, —Cl, —Br or —I. Two simple members of this class are methyl chloride (CH3CI) and ethyl chloride (CH3CH2CI). 

As an example of the chlorine chemistry, consider the chlorination of methane. The chlorination reaction, which proceeds at temperatures above 1200 K, consists of two main stages [285], The first involves formation of methyl chloride (CH3CI) from methane. It is initiated by dissociation of a chlorine molecule,... 

V11—18.1. Methyl Chloride (CH3CI), Methyl Bromide (CH3Br)... 

The halocarbons, which are not destroyed in the troposphere by reactions with hydroxyl, pass into the stratosphere where they are photo-dissociated to liberate chlorine atoms which attack ozone. Only one of them is of natural origin, methyl chloride CH3CI, but there are also several industrial products, especially carbon tetrachloride, CC14, trichlorofluo-romethane, CFC13, and dichlorodifluoromethane. Methyl chloride (Table III) has a natural marine origin (for details, see ref. 12), but it is certainly present also in the smoke produced when polyvinyl and other products containing chlorine are burnt. In addition, it is produced naturally not only in forest fires, but also in tropical agriculture based on the cultivation... 

In an engineering analysis, the liquid density is needed for methyl chloride (CH3CI) at 343.15 K. Determine the liquid density of methyl chloride at this temperature. 

Methane, methyl chloride (CH3CI) and bromochloromethane (CH2ClBr) are each achiral. Bromochloromethane, however, has the property that further substitution of one of the two hydrogen atoms (by other than... 

Methyl Chloride CH3CI with a content of >99.6% was dried over molecular sieve 4A. 

The successive substitution of methane hydrogens with chlorine produces a mixture of four chloromethanes, namely, monochloromethane (methyl chloride, CH3CI), dichloromethane (methylene chloride, CH2C12), trichloromethane (chloroform, CHCI3), and tetrachloromethane (carbon tetrachloride, CCI4). Each of these four compounds has many industrial applications. 

In the second step of the operation, the inert gas is replaced by methyl chloride (CH3CI), and the flnidizing conditions are maintained so that the gas-phase concentration is nniform. The following gas-solid reaction occurs ... 

Methyl chloride ch3ci 0.5 (partly of natural origin)... 

The first-order rate constant for the reaction of methyl chloride (CH3CI) with water to produce methanol (CH3OH) and hydrochloric acid (HCl) is 3.32 X 10 ° s at 25°C. Calculate the rate constant at 40°C if the activation energy is 116 kJ/mol. 

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