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Chlorinity definition

Pamphlet 100, Solubility of Dry Chlorine, Definition and Analytical Issues, The Chlorine Institute, Inc., 2001 L Street, NW, Washington, DC 20036. [Pg.331]

Only chloric(III) acid, HCIO2, is definitely known to exist. It is formed as one of the products of the reaction of water with chlorine dioxide (see above). Its salts, for example NaClOj, are formed together with chlorates)V) by the action of chlorine dioxide on alkalis. Sodium chlorate(III) alone may be obtained by mixing aqueous solutions of sodium peroxide and chlorine dioxide ... [Pg.339]

Figure 5-16. Structure editor of the CrossFire ComiTiander V6, showing the definition ofan atom list (consisting of hydrogen and chlorine atoms) for polychlorinated biphenyls. Figure 5-16. Structure editor of the CrossFire ComiTiander V6, showing the definition ofan atom list (consisting of hydrogen and chlorine atoms) for polychlorinated biphenyls.
Fn some cases, r-allylpalladium complex formation by retention syn attack) has been observed. The reaction of the cyclic allyiic chloride 33 with Pd(0) affords the 7r-allylpalladium chlorides 34 and 35 by retention or inversion depending on the solvents and Pd species. For example, retention is observed in benzene, THF, or dichloromethane with Pd2(dba)3. However, the complex formation proceeds by inversion in these solvents with Pd(Ph3P)4, whereas in MeCN and DMSO it is always inversion[33]. The syn attack in this case may be due to coordination of Pd to chlorine in 33, because Pd is halophilic. The definite syn attack in complex formation has been observed using stereoche-mically biased substrates. The reaction of the cxoallylic diphenylphosphino-acetate 36 with phenylzinc proceeds smoothly to give 37. The reaction can be explained by complex formation by a syn mechanism[31]. However, these syn attacks are exceptional, and normally anti attack dominates. [Pg.297]

Salt was first electrochemicaHy decomposed by Cmickshank ia 1800, and ia 1808 Davy confirmed chlorine to be an element. In the 1830s Michael Faraday, Davy s laboratory assistant, produced definitive work on both the electrolytic generation of chlorine and its ease of Hquefaction. And ia 1851 Watt obtained the first Fnglish patent for an electrolytic chlorine production cell (11). [Pg.486]

Given stringent requirements for effective sensitizers and the desire to use wavelengths further to the red for therapeutic appHcations, definition of newer sensitizers has been a principal area of research since about 1987. Expanded theoretical and experimental understanding of photophysics has been a key element in identifying new classes of potential sensitizers (93—98). Research has focused on cationic derivatives of Nile Blue (93), metaHo-phthalocyanines (94), naphthalocyanines (95), chlorin-type compounds (96), expanded ring porphyrinoids (97), as well as porphyrins other than hematoporphyrin and its derivatives (98). This work has also been reviewed (10,91). Instmmentation for photodynamic therapy has been reviewed (99). [Pg.395]

The total concentration or amount of chlorine-based oxidants is often expressed as available chorine or less frequendy as active chlorine. Available chlorine is the equivalent concentration or amount of Cl needed to make the oxidant according to equations 1—4. Active chlorine is the equivalent concentration or amount of Cl atoms that can accept two electrons. This is a convention, not a description of the reaction mechanism of the oxidant. Because Cl only accepts two electrons as does HOCl and monochloramines, it only has one active Cl atom according to the definition. Thus the active chlorine is always one-half of the available chlorine. The available chlorine is usually measured by iodomettic titration (7,8). The weight of available chlorine can also be calculated by equation 5. [Pg.142]

Some authorities question whether dmnkeimess can result from the inhalation of ethyl alcohol vapors. Experience has demonstrated that in any event such intoxication is indeed rare (281). There is no concrete evidence that the inhalation of ethyl alcohol vapor will cause cirrhosis. Liver function is definitely impaired during alcohol intoxication (282), making the subject more susceptible to the toxic effects of chlorinated hydrocarbons. [Pg.414]

Rejection Rejection is defined in Background and Definitions. The highest-rejection membranes are those designed for single-pass production of potable water from the sea. The generally accepted criterion is 99.4 percent rejection of NaCl. Some membranes, notably cellulose triacetate fibers are rated even higher. A whole range of membranes is available as rejection requirements ease, and membranes with excellent chlorine resistance and hydrolytic stability can be made with salt rejection over 90 percent. [Pg.2036]

The white solid which collects inside the upper part of the flask is methylsulfur trichloride. This must be washed down with the cold reaction mixture before the flask warms to room temperature. The progress of the chlorination is accompanied by definite color changes. When one-third of the chlorine has been added, the reaction mixture is a deep reddish orange color which gradually fades as more chlorine is added until at the end the color should be a pale golden yellow or light straw color. [Pg.64]

Ocean sea water is roughly equivalent in strength to a 3 j % w/v solution of sodium chloride, but it has a much more complex composition, embodying a number of major constituents, and traces at least of almost all naturally occurring elements. For convenience, however, the concentration of salts in any sample of sea water is expressed in terms of the chloride content, either as chlorinity or as salinity. Both these units are again subject to arbitrary definition and do not conform simply to the chemical composition. [Pg.364]

Based on these definitions, the chlorination reaction of methane to yield chloromethane is an oxidation because a C-H bond is broken and a C—Cl bond... [Pg.348]

Pure sodium chloride, like pure water, has a definite melting (freezing) temperature (at a given pressure). Separating operations—such as distilling or freezing—do not separate the salt into components. The composition of the salt, whether expressed in relative numbers of sodium and chlorine atoms or in the relative weights of these atoms, is fixed and is represented by the formula NaCl. Sodium chloride, like water, is an example of a pure substance. [Pg.71]

Chlorambucil - there is no problem with the quantitation ion (at m/z 254), although the second ion proves to be a little difficult. While the ion at m/z 303 is the obvious choice, this is not very intense and therefore for samples containing small amounts of analyte the precision of measurement of this ion will be reduced and it may not be detectable at all levels at which the quantitation ion is observed. We could possibly consider the (M- -2) ion, as the combination o/m/z 254 (high mass, and therefore reasonable specificity), the presence of one chlorine, and the chromatographic retention time could be considered sufficient for definitive identification in those cases in which the intensity o/m/z 303 is insufficient. [Pg.73]

A limited number of pure substances are available from NIST, primarily clini-cally-relevant compounds such as cholesterol, urea, uric acid, creatinine, glucose, cortisol, tripalmitin, and bilirubin (NIST SRM website). These compounds are certified for purity (greater than 99 %) and are used as primary calibrants in definitive methods for these clinical analytes (see below). Several additional pure substances are available for specific applications such as microchemistry, i.e. elemental composition (acetanilide, anisic acid, cystine nicotinic acid, o-bromobenzoic acid, p-fluoro-benzoic acid, m-chlorobenzoic acid), polarimetric standards (sucrose and dextrose), acidimetric standard (benzoic acid and boric acid). Only three pure substance NIST RMs are available for environmental contaminants, namely the chlorinated pesticides, lindane, 4,4 -DDT, and 4,4 -DDE. [Pg.85]

Those ions which take no part in the reaction are known as spectator ions , and from these considerations, the following definitions can be derived. A basic oxide (or hydroxide) is a metallic oxide (or hydroxide) which contains the 02 (or OFT) ion it will react with an acid to form a salt and water only. It is necessary to realize the importance of the word only in this definition, as were it to be omitted, then certain compounds which are quite different from basic metallic oxides and hydroxides would be covered by this definition. Thus, Pb(IV) oxide reacts with hydrochloric acid to produce Pb(II) chloride (a salt) and water, but does not belong to the class of bases because chlorine gas is also produced ... [Pg.591]

A definite decomposition voltage occurs for the following reason. As soon as there is a potential difference between the electrodes, H+ ions move to the cathode and Cl ions to the anode. The ions are discharged, forming layers of adsorbed gas on the inert metal surfaces. This essentially amounts to having a hydrogen electrode and a chlorine electrode in place of the two platinum electrodes. The outcome is a typical chemical cell ... [Pg.679]

The chlorine ion can now accept a proton (and become hydrochloric acid again). If the chlorine can accept a proton, according to the Bronsted-Lowry definition, it is a base. Chemists actually call this chlorine ion the conjugate base of hydrochloric acid. Any time an acid gives up its proton, the substance that is left over can act as a base. So every acid has a conjugate base. [Pg.24]

Tsirelson, V.G., Zou, P.F. and Bader, R.F.W. (1995) Topological definition of crystal structure determination of the bonded interactions in solid molecular chlorine, Ada Cryst., A51, 143-153. [Pg.124]

By definition, any pesticide has toxic effects on organisms. Listed pesticides are those that combine high toxicity with resistance to degradation in the environment. Moore and Ramamoorthy109 review the behavior of chlorinated pesticides in natural waters. [Pg.825]


See other pages where Chlorinity definition is mentioned: [Pg.92]    [Pg.253]    [Pg.508]    [Pg.334]    [Pg.261]    [Pg.26]    [Pg.345]    [Pg.131]    [Pg.416]    [Pg.170]    [Pg.164]    [Pg.1024]    [Pg.87]    [Pg.26]    [Pg.314]    [Pg.624]    [Pg.673]    [Pg.616]    [Pg.30]    [Pg.192]    [Pg.136]   
See also in sourсe #XX -- [ Pg.601 ]




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