Lithium fluoride, chloride, bromide

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 bromide Aluminum chloride... 

The Equation of State of the Alkali Halides.—The alkali halides, the fluorides, chlorides, bromides, and iodides of lithium, sodium, potassium, rubidium, and caesium have been more extensively studied experimentally than any other group of ionic crystals. For most of these materials, enough data are available to make a fairly satisfactory comparison between experiment and theory. The observations include the compressibility and its change with pressure, at room temperature, from which the quantities ai(T), o2(r) of Eq. (1.1), Chap. XIII, can be found... 

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. 

In lithium chloride, bromide and iodide, magnesium sulfide and selenide and strontium chloride the inter-atomic distances depend on the anion radius alone, for the anions are in mutual contact the observed anion-anion distances agree satisfactorily with the calculated radii. In lithium fluoride, sodium chloride, bromide and iodide and magnesium oxide the observed anion-cation distances are larger than those calculated because of double repulsion the anions are approaching mutual contact, and the repulsive forces between them as well as those between anion and cation are operative. 

The formyl group provides enough activation so that lithium fluoride will convert 5-bromofuran-2-carboxaldehyde into 5-fluorofuran-2-carboxalde-hyde, but only in dimethylformamide at 100°C. Other metal cations are ineffective. Replacement by other halogens is easy, the chloride-bromide displacement being reversible.180... 

Lithium fluoride cannot displace less reactive halogens from aryl chlorides and bromides. However, a high-temperature reaction of lithium fluoride with bromoform gives a few percent exchange along with considerable side products.3 By passing a stream of methyl chloride in a lithium fluoride/sodium fluoride/potassium fluoride melt at 500 C a conversion rate of 42% to methyl fluoride in 85% yield is observed.4... 

H. Stamm also measured the solubilities of the salts of the alkalies in liquid ammonia —potassium hydroxide, nitrate, sulphate, chromate, oxalate, perchlorate, persulphate, chloride, bromide, iodide, carbonate, and chlorate rubidium chloride, bromide, and sulphate esesium chloride, iodide, carbonate, and sulphate lithium chloride and sulphate sodium phosphate, phosphite, hypophosphite, fluoride, chloride, iodide, bromate, perchlorate, periodate, hyponitrire, nitrite, nitrate, azide, dithionate, chromate, carbonate, oxalate, benzoate, phtnalate, isophthalate ammonium, chloride, chlorate, bromide, iodide, perchlorate, sulphate, sulphite, chromate, molybdate, nitrate, dithionate, thiosulphate, persulphate, thiocyanate, phosphate, phosphite, hypophosphite, arsenate, arsenite, amidosulphonate, ferrocyanide, carbonate, benzoate, methionate, phenylacetate, picrate, salicylate, phenylpropionate, benzoldisulphonate, benzolsulphonate, phthalate, trimesmate, mellitate, aliphatic dicarboxylates, tartrate, fumarate, and maleinate and phenol. 

Most ionic halides dissolve in water to give hydrated metal ions and halide ions. However, the lanthanide and actinide elements in the +3 and +4 oxidation states form fluorides insoluble in water. Fluorides of Li, Ca, Sr, and Ba also are sparingly soluble, the lithium compound being precipitated by ammonium fluoride. Lead gives a sparingly soluble salt PbCIF, which can be used for gravimetric determination of F . The chlorides, bromides, and iodides of Ag1, Cu1, Hg1, and Pbn are also quite insoluble. The solubility through a series of mainly ionic halides of a... 

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. 

Lithium is the only lA metal that combines with N2 to form a nitride, Li3N. Magnesium readily forms magnesium nitride, MgjN2. Both metals readily combine with carbon to form carbides, whereas the other alkali metals do not react readily with carbon. The solubilities of Li compounds are closer to those of Mg compounds than to those of other lA compounds. The fluorides, phosphates, and carbonates of both Li and Mg are only slightly soluble, but their chlorides, bromides, and iodides are very soluble. Both Li and Mg form normal oxides, Li20 and MgO, when burned in air at 1 atmosphere pressure. The other alkali metals form peroxides or superoxides. 

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. 

Potassium fluoride on alumina is sometimes used as a base.23 It may be that the fluoride ion displaces some surface hydroxyl from the alumina to produce some potassium hydroxide. Lithium chloride, bromide, and iodide on silica... 

Iron(II) fluoride Iron(II) hydroxide Iron(III) hydroxide Iron(III) phosphate dihydrate Lanthanum iodate Lead(II) bromide Lead(II) carbonate Lead(II) chloride Lead(II) fluoride Lead(II) hydroxide Lead(II) iodate Lead(II) iodide Lead(II) selenate Lead(II) sulfate Lithium carbonate Lithium fluoride Lithium phosphate Magnesium carbonate Magnesium carbonate trihydrate... 

Write the chemical formula for each of the following compounds (a) lithium fluoride (b) zinc oxide (c) barium hydroxide (d) magnesium bromide (e) hydrogen cyanide (f) copper(I) chloride. 

FIG. 10. Plots of enthalpy interaction parameters for liquid mixtures of magnesium fluoride, chloride, and bromide with corresponding lithium, sodium and potassium salts. 

The electrolyte used in lithium (aluminium)-iron sulphide secondary cells is commonly a mixture of lithium chloride and potassium chloride. A lithium fluoride-lithium chloride-lithium bromide mixture has also been used. With the latter electrolyte the discharge occurs in two steps ... 

Its high decomposition potential allows the use of alkali earth electrodes. At the working temperature of 400-600 C it is almost fully ionized. Various other electrolytes arc now being studied including lithium chloride-lithium bromide, lithium fluoride-sodium fluoride-potassium fluoride (both liquid electrolytes which can be solidified by adding about 35% magnesium oxide). Lithium iodide-alumina solid electrolyte is also being studied. 

Clusius K, Goldmann J, Perlick A (1949) Low- temperature research. VII. The specific heat of the alkali halides lithium fluoride, sodium chloride, potassium chloride, potassium bromide, potassium iodide, rubidium bromide, and rubidium iodide between 10° and 273° abs. Z Naturforsch 4a 424—432... 

A. Idris, I. Ahmed, M.A. Limin, Influence of lithium chloride, lithium bromide and lithium fluoride additives on performance of polyethersulfone membranes and its application in the treatment of palm oil mill effluent, Desalination, 250 (2010) 805-809. 

Metal halide salts other than sodium iodide have been used sparsely to prepare halodeoxy sugars from sulfonate esters. Lithium chloride (107) and lithium bromide (33) have found limited application. Potassium fluoride (dihydrate) in absolute methanol has been used (51, 52) to introduce fluorine atoms in terminal positions of various D-glucose derivatives. The reaction is conducted in sealed tube systems and requires... 

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