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Chlorine elements

The chlorine content can be determined by either chlorine elemental analysis or a potentiometric titration using a chloride-ion electrode. For titration, about 0.2 g. of polymer is heated in 3 ml. of pyridine at 100° for 2 hours. This suspension is then transferred to a 50-mi. beaker containing 30 ml. of aqueous 50% acetic acid and 5 ini. of concentrated nitric acid, and the resulting mixture is titrated against aqueous 0.1 N silver nitrate. [Pg.98]

Fig. 12 EDX chlorine elemental maps showing (a) even dispersion of drug in tablet and (b) large concentrated areas of active drug. Fig. 12 EDX chlorine elemental maps showing (a) even dispersion of drug in tablet and (b) large concentrated areas of active drug.
Materials. GMC and PCLS were synthesized by free radical solution polymerization initiated by benzoyl peroxide as described previously (5,6). Nearly mono and polydisperse polystyrenes were obtained from Pressure Chemical Co. and the National Bureau of Standards respectively. Molecular weight and polydispersity were determined by gel permeation chromatography (GPC) using a Water Model 244 GPC, equipped with a set (102-106 A) of —Styragel columns using THF as the elution solvent. The molecular parameters of the above three polymers are listed in Table I. The copolymer, poly(GMA-co-3-CLS), contained 53.5 mole % 3-CLS and 46.5 mole % GMA, as determined by chlorine elemental analysis. The structure of the copolymer is shown in Figure 1. [Pg.242]

Gribble GW (1999) Chlorine - Element from Hell or Gift from God The Scientific Side of the Chlorine Story. Technology 6 193... [Pg.381]

The recent developments in fluorine chemistry raise the possibility of using this halogen as an oxidant. Its action should be very much stronger than that of chlorine elemental fluorine easily displaces oxygen from water. It may be difScult to control such a powerful oxidant in such a manner as to produce limited oxidation of organic compounds. [Pg.133]

Quaternization Reaction. In a pressure bottle equipped with a magnetic stirrer, the copolymer was dissolved in methanol, and methyl chloride was then added to slight excess. For reaction conditions, see Table VI. After the specified reaction time, the excess methyl chloride was allowed to evaporate, and the polymer was isolated by precipitation into acetone. After purification, the quaternized copolymer was characterized by IR and chlorine elemental analysis. Similar experiments were conducted using equimolar amounts of methyl chloro-acetate. [Pg.146]

This type of E/pHdiagram, also called Pourbaix diagram, is frequently used for redox equilibria in solutions, and also in the field of corrosion studies. It is a graphic illustration of thermodynamic data which results from applying the Nernst law. Section 3.4.1.4 focuses on the example of a particular part of the Pourbaix diagram which deals with the chlorine element in aqueous solution. Numerous other examples can easily be found in scientific literature. [Pg.59]

Oxidation numbers of elements in compounds generally increase regularly as you move across periods 2 and 3 in the periodic table (Table 9.2). For example, the maximum oxidation number of the elements in oxides increases from +1 in sodium to +7 for chlorine. Elements not in the transition block are known as main group elements. [Pg.302]

Consider as another example common table salt, a highly stable compound composed of sodium and chlorine. Elemental sodium, by contrast, is a highly reactive, silvery metal that can explode on contact with water. Elemental chlorine is a corrosive, greenish-yellow gas that can be fatal if inhaled. Yet the compound formed from the combination of these two elements is sodium chloride (or table salt), a flavor enhancer that tastes great on steak. [Pg.88]

Figure 2.7 Mass spectrum of chlorine. Elemental chlorine (CI2) contains only two isotopes 34.97 amu (75.53%) and 36.97 amu (24.47%). Figure 2.7 Mass spectrum of chlorine. Elemental chlorine (CI2) contains only two isotopes 34.97 amu (75.53%) and 36.97 amu (24.47%).
CH2CI-CO-CH3. Colourless lachrymatory liquid b.p. 119°C. Manufactured by treating propanone with bleaching powder or chlorine. It is used as a tear gas and is usually mixed with the more potent bromoacetone. chloro acids Complex chloroanions are formed by most elements of the periodic table by solution of oxides or chlorides in concentrated hydrochloric acid. Potassium salts are precipitated from solution when potassium chloride is added to a solution of the chloro acid, the free acids are generally unstable. [Pg.93]

The basic characters from which the notations are constructed comprise the upper-case letters A-Z of the alphabet, the numerals zero (symbolized 0) to nine (0-9), three punctuation marks hyphen (-), ampersand ( ) and oblique (/) and a blank space. Many of the normal atomic symbols such as B, F, P, 1, etc., are also employed unchanged but frequently occurring important elements and groups are assigned a single letter notation (e.g. chlorine sG ... [Pg.426]

Figure Bl.25.2 shows the XPS spectra of two organoplatinum complexes which contain different amounts of chlorine. The spectrum shows the peaks of all elements expected from the compounds, the Pt 4f and 4d doublets (the 4f doublet is iimesolved due to the low energy resolution employed for broad energy range scans). Cl 2p and Cl 2s, N Is and C Is. Flowever, the C Is caimot be taken as characteristic for the complex only. All surfaces that have not been cleaned by sputtermg or oxidation in the XPS spectrometer contain carbon. The reason is that adsorbed hydrocarbons from the atmosphere give the optimum lowering of the surface free energy and hence, all surfaces are covered by hydrocarbon fragments [9]. Figure Bl.25.2 shows the XPS spectra of two organoplatinum complexes which contain different amounts of chlorine. The spectrum shows the peaks of all elements expected from the compounds, the Pt 4f and 4d doublets (the 4f doublet is iimesolved due to the low energy resolution employed for broad energy range scans). Cl 2p and Cl 2s, N Is and C Is. Flowever, the C Is caimot be taken as characteristic for the complex only. All surfaces that have not been cleaned by sputtermg or oxidation in the XPS spectrometer contain carbon. The reason is that adsorbed hydrocarbons from the atmosphere give the optimum lowering of the surface free energy and hence, all surfaces are covered by hydrocarbon fragments [9].
Among the non-metals, nitrogen and chlorine, for example, are gases, but phosphorus, which resembles nitrogen chemically, is a solid, as is iodine which chemically resembles chlorine. Clearly we have to consider the physical and chemical properties of the elements and their compounds if we are to establish a meaningful classification. [Pg.1]

From the tables it is clear that elements in Groups I-IV can display a valency equal to the group number. In Groups V-VII. however, a group valency equal to the group number (x) can be shown in the oxides and fluorides (except chlorine) but a lower valency (8 — x) is displayed in the hydrides. This lower valency (8 — x) is also found in compounds of the head elements of Groups V-VII. [Pg.20]

Let us consider the formation of sodium chloride from its elements. An energy (enthalpy) diagram (called a Born-Haber cycle) for the reaction of sodium and chlorine is given in Figure 3.7. (As in the energy diagram for the formation of hydrogen chloride, an upward arrow represents an endothermic process and a downward arrow an exothermic process.)... [Pg.73]

Both boron and aluminium chlorides can be prepared by the direct combination of the elements. Boron trichloride can also be prepared by passing chlorine gas over a strongly heated mixture of boron trioxide and carbon. Like boron trifluoride, this is a covalent compound and a gas at ordinary temperature and pressure (boiling point 285 K). It reacts vigorously with water, the mechanism probably involving initial co-ordination of a water molecule (p, 152). and hydrochloric acid is obtained ... [Pg.154]

The affinity of chlorine for hydrogen is so great that chlorine will react with many compounds containing this element, for example hydrocarbons (a wax taper burns in chlorine). [Pg.321]

Chlorine reacts with most elements, both metals and non-metals except carbon, oxygen and nitrogen, forming chlorides. Sometimes the reaction is catalysed by a trace of water (such as in the case of copper and zinc). If the element attacked exhibits several oxidation states, chlorine, like fluorine, forms compounds of high oxidation state, for example iron forms iron(III) chloride and tin forms tin(IV) chloride. Phosphorus, however, forms first the trichloride, PCI3, and (if excess chlorine is present) the pentachloride PCI5. [Pg.322]

Bromine has a lower electron affinity and electrode potential than chlorine but is still a very reactive element. It combines violently with alkali metals and reacts spontaneously with phosphorus, arsenic and antimony. When heated it reacts with many other elements, including gold, but it does not attack platinum, and silver forms a protective film of silver bromide. Because of the strong oxidising properties, bromine, like fluorine and chlorine, tends to form compounds with the electropositive element in a high oxidation state. [Pg.322]

Many of the reactions of halogens can be considered as either oxidation or displacement reactions the redox potentials (Table 11.2) give a clear indication of their relative oxidising power in aqueous solution. Fluorine, chlorine and bromine have the ability to displace hydrogen from hydrocarbons, but in addition each halogen is able to displace other elements which are less electronegative than itself. Thus fluorine can displace all the other halogens from both ionic and covalent compounds, for example... [Pg.325]

In order to allow any multiple chlorination of the biphenyl skeleton, the user may define an atom list (eonsisting of hydrogen and chlorine atoms) and substitute all H-atoms by this list. One may click on the drop-down selection box behind the element icons, select the options Generics. .set the user-defined atom to A1 and quit by the OK button. As a result this atom selection is active for the subsequent drawing steps. After this atom list is drawn ten times as the ten substituents, its composition has to be defined by clicking the A, icon on the left-hand side of the structure editor and by selecting H and Cl in the periodic table (Figure 5-16). [Pg.250]


See other pages where Chlorine elements is mentioned: [Pg.52]    [Pg.58]    [Pg.325]    [Pg.1381]    [Pg.4]    [Pg.64]    [Pg.161]    [Pg.33]    [Pg.107]    [Pg.192]    [Pg.52]    [Pg.58]    [Pg.325]    [Pg.1381]    [Pg.4]    [Pg.64]    [Pg.161]    [Pg.33]    [Pg.107]    [Pg.192]    [Pg.92]    [Pg.93]    [Pg.189]    [Pg.199]    [Pg.1372]    [Pg.14]    [Pg.21]    [Pg.28]    [Pg.72]    [Pg.196]    [Pg.310]    [Pg.313]    [Pg.327]    [Pg.253]   
See also in sourсe #XX -- [ Pg.248 ]

See also in sourсe #XX -- [ Pg.43 ]




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