Potassium bromide fluoride

Alkyl fluorides have been prepared by reaction between elementary fluorine and the paraffins, by the addition of hydrogen fluoride to olefins, by the reaction of alkyl halides with mercurous fluoride, with mercuric fluoride, with silver fluoride, or with potassium fluoride under pressure. The procedure used is based on that of Hoffmann involving interaction at atmospheric pressure of anhydrous potassium fluoride with an alkyl halide in the presence of ethylene glycol as a solvent for the inorganic fluoride a small amount of olefin accompanies the alkyl fluoride produced and is readily removed by treatment with bromine-potassium bromide solution. Methods for the preparation of alkyl monofluorides have been reviewed. ... 

Due to the above requirements, typical optically-transparent materials, such as oxides (glass, quartz, alumina, zirconium oxide etc.) and halides (sodium chloride, lithium fluoride, calcium fluoride, potassium bromide, cesium bromide etc.) are usually unsuitable for use with fluoride melts. Therefore, no standard procedure exists at present for the spectral investigation of fluoride melts, and an original apparatus must be created especially for each particular case. 

Fluoride ion is effective in promoting the reduction of aldehydes by organosil-icon hydrides (Eq. 161). The source of fluoride ion is important to the efficiency of reduction. Triethylsilane reduces benzaldehyde to triethylbenzyloxysilane in 36% yield within 10-12 hours in anhydrous acetonitrile solvent at room temperature when tetraethylammonium fluoride (TEAF) is used as the fluoride ion source and in 96% yield when cesium fluoride is used.83 The carbonyl functions of both p-anisaldehyde and cinnamaldehyde are reduced under similar conditions. Potassium bromide or chloride, or tetramethylammonium bromide or chloride are not effective at promoting similar behavior under these reaction conditions.83 Moderate yields of alcohols are obtained by the KF-catalyzed PMHS, (EtO SiH, or Me(EtO)2SiH reduction of aldehydes.80,83,79... 

Examples of the Michael-type addition of carbanions, derived from activated methylene compounds, with electron-deficient alkenes under phase-transfer catalytic conditions have been reported [e.g. 1-17] (Table 6.16). Although the basic conditions are normally provided by sodium hydroxide or potassium carbonate, fluoride and cyanide salts have also been used [e.g. 1, 12-14]. Soliddiquid two-phase systems, with or without added organic solvent [e.g. 15-18] and polymer-supported catalysts [11] have been employed, as well as normal liquiddiquid conditions. The micellar ammonium catalysts have also been used, e.g. for the condensation of p-dicarbonyl compounds with but-3-en-2-one [19], and they are reported to be superior to tetra-n-butylammonium bromide at low base concentrations. 

Infrared detectors are similar in construction to those used in UV detection. The main difference is that the sample cell windows are constructed of sodium chloride, potassium bromide, or calcium fluoride. A limitation of this type of detector is caused by the low transparency of many useful solvents (Skoog et al., 1998). Recent changes to interface systems that use spraying to induce rapid evaporation of the solvent provide good sensitivity and enhanced spectral quality (LaCourse, 2000). 

The typical V-curve for eutectic mixtures is obtained with mixtures of potassium chloride with 39 per cent, of potassium fluoride at 605° 76 of potassium bromide at 740° 69 3 of potassium iodide at 580° and 42 8 of potassium sulphate at 705°. Results with binary mixtures of the alkali chlorides are indicated in the accompanying Table XVIII, where the eutectic temp, is bracketed with the atomic percentage of the element indicated on the same horizontal line S means that an unbroken series of solid soln. are formed otherwise, solid soln. are wanting. 

Table 5), and several are now being used, or are potentially useful, for measuring key ocean elements. The most common use of direct potentiometry (as compared with potentiometric titrations) is for measurement of pH (Culberson, 1981). Most other cation electrodes are subject to some degree of interference from other major ions. Electrodes for sodium, potassium, calcium, and magnesium have been used successfully. Copper, cadmium, and lead electrodes in seawater have been tested, with variable success. Anion-selective electrodes for chloride, bromide, fluoride, sulfate, sulfide, and silver ions have also been tested but have not yet found wide application. 

IONIC CRYSTAL. A crystal ihut consists effectively of ions bound lugclher by Iheir electrostatic attraction. Examples of such crystals are the alkali halides, including potassium fluoride, potassium chloride, potassium bromide, potassium iodide, sodium fluoride, and the other combinations of sodium, cesium, rubidium or lithium ions with fluoride, chloride, bromide or iodide ions. Many other types of ionic crystals are known,... 

Lithium fluoride, calcium fluoride and potassium bromide prisms are used to study with high resolution the absorption characteristics of compounds in specified regions (usually in conjunction with diffraction gratings), e.g. 4000-1700,4200-1300,1100-385 cm 1 respectively. 

Treatment of aryl tellurium trichlorides with silver fluoride, potassium bromide, or potassium iodide causes chlorine to be exchanged for other halogens (see p. 320). The reaction of 4-ethoxyphenyl tellurium trichloride with silver acetate gave a compound of indefinite composition6. 

Nomenclature of Salts. — Salts containing only two elements follow the rule for binary compounds, aiid hence end in -ide. This suffix is added to an abbreviated form of the name of the non-metal, e.g. chloride, bromide, duor-ide, etc. Notice that the prefix hydro- is omitted, and that the name of the metal precedes, c.g. sodium chloride, potassium bromide, calcium fluoride, etc. It will soon be shown experimentally that salts may be regarded as derived from... 

Fluorine and bromine.—While no sensible reaction between fluorine and chlorine has been observed, H. Moissan found that fluorine unites violently with cold bromine vapour, and the reaction is attended by une jiamme eclair ante, but with the evolution of little heat. P. Lebeau found that no flame is produced if dry liquid bromine is employed, and he showed that the product of the reaction is bromine trifluoride BF3, a result almost simultaneously established by E. B. E. Prideaux. No reaction —solvent or chemical—occurs between liquid fluorine and solid bromine, and the fluorine can be distilled from the latter without any sign of interaction. There is no indication of the formation of a lower bromide, say, BrF and attempts to prepare a higher fluoride, say BrF4, by passing a large excess of fluorine over the trifluoride, were fruitless. Bromine trifluoride was also made by the action of fluorine on potassium bromide KBr-[-2F2=KF+BrF3. 

When refractory linings are intended to contain moderate to high temperature environments having products of combustion or reaction containing compounds of sodium, lithium, potassium, vanadium and titanium and bromides, fluorides, chlorides, sulfides, phosphates along with the usual CO2, CO, H2, and O2, extreme care must be taken in their design. In these highly corrosive atmospheres, refractories perform differently than they do in clean environments. 

Phosf orus fluoride (PF) FjPjCg) 1044 Potassium bromide (133r) Br K (g) 438... 

The electronegativity differences in lithium fluoride, sodium chloride, and potassium bromide show that they are best represented as ionic compounds. 

Figure 9.6 compares the formation of sodium chloride with the formation of lithium fluoride and potassium bromide. For each of these salts, the AENs are equal to or greater than 2.0. Like sodium chloride, both lithium fluoride and potassium bromide are considered mostly ionic compounds. Notice that the two atoms in each bond are well separated from each other on the periodic table. 

Magnesium is the third most abundant element in seawater, behind sodium and chorine, and has an average concentration of approximately 1300 ppm. Table 3.2 displays the major and some minor elemental constituents of seawater. Eleven major constituent ions account for 99.5% of the total solutes present in seawater. These 11 are chloride, sulfate, bicarbonate, bromide, fluoride, sodium, magnesium, calcium, potassium, strontium, and boron, and they largely determine the chemistry of seawater. 

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