Barium, in liquid

The spectra of dilute solutions of lithium, sodium, potassium, calcium, and barium in liquid deutero-ammonia indicate that the absorbing species is the same in each case. The dependence of the shape, intensity, and energy of the absorption band on temperature was investigated for sodium-ND3 solutions. The data are discussed in terms of the electron-in-a-cavity model. No spectral evidence was found for the presence of new species in ND3 solutions containing mixtures of sodium and sodium iodide. 

Unfortunately, liquid ammonia possesses a very intense absorption band at 15,320 A. (2 i and/or 2vz) so that this region is inaccessible for quantitative measurements even with a 1 mm. cell. If ND8 is used as the solvent instead of NH8, no intense overtone or combination bands of the solvent occur in the spectral region of interest (Figure 1). The spectra of dilute solutions of lithium, sodium, potassium, calcium, and barium in liquid ND8, and the perturbations arising from concentration changes, temperature changes, and the presence of inert salts have been investigated. 

The reaction of hydrogen sulphide with solutions of calcium, strontium, or barium in liquid ammonia has been shown205 to give precipitates of the... 

A very strong reducing agent and the presence of suitable dopant counterions are needed to introduce divalent cations into polyacetylene. Such a strong reducing solution can be made by dissolving the alkaline earth metals, calcium, strontium or barium in liquid ammonia (equation 1). 

The first well-authenticated preparation of the [Cr(C0)5] anion was carried out by Behrens and Weber (41) and involved the reduction of chromium hexacarbonyl with elemental sodium, lithium, calcium, or barium in liquid ammonia solution. It is not surprising that such a powerful reducing agent is necessary to effect the reduction of the very stable hexacoordinate chromium hexacarbonyl to the less stable pentacoordinate [Cr(CO)s] anion. In a subsequent report by Podall and associates the reduction of chromium hexacarbonyl with sodium amalgam in tetrahydrofuran or diglyme solution (42) is described. The same report also describes the direct preparation of the [Cr(CO)s] anion from chromium trichloride by treatment with elemental sodium in diglyme solution under carbon monoxide pressure. 

The fullerenes Ceo and C70 are discussed in Chapter 14. When these fullerenes are reduced using barium in liquid... 

Weiss ° treated 16-dehydro- (6), 17a-acetoxy- (8), 17a-hydroxy- (9) and 17a-bromopregnan-20-one (11) with a solution of lithium, barium, calcium or sodium in liquid ammonia and reacted the intermediate enolate anion (7) with the appropriate alkyl halide. 

One of the most common techniques for preparing Zintl phases is by the reaction of a solution of the alkali metal in liquid ammonia with the other element. However, many of these materials are obtained by heating the elements. For example, heating barium with arsenic leads to the reaction... 

Alkylpyridines are aminated preferentially at the 2-position, but reaction is slower than in the parent system. Quinoline is difficult to aminate and only a low yield of 2-aminoquinoline (32%) is obtained from reaction with sodamide in toluene. When dimethylaniline is employed as solvent, 2-amino-3,4-dihydroquinoline (24%) becomes the major product, and the yield of 2-aminoquinoline drops to 7%. The best yields of 2-aminoquinoline (53-69%) have been obtained by using barium or potassium amide in liquid ammonia. Use of the potassium salt also produces a 10% yield of the 4-amino isomer. The... 

Hydrofluoric acid like water is an associated liquid, and even the gas, as we shall soon see, is associated. It has the power of uniting with fluorides. It also seems to be an ionizing solvent for a soln. of potassium fluoride in liquid hydrogen fluoride is an excellent conductor it also possesses marked solvent powers. According to E. C. Franklin,7 the liquid readily dissolves potassium fluoride, ehloride, and sulphate sodium fluoride, bromide, nitrate, chlorate, and bromate acetamide and urea. The solvent action is not so marked with barium fluoride, cupric chloride, and silver cyanide while calcium and lead fluorides copper sulphate and nitrate ferric chloride, mercuric oxide, and magnesium metal, are virtually insoluble in this menstruum. Glass also is not affected by the liquid if moisture be absent. The liquid scarcely acts on most of the metals or non-metals at ordinary temp., though it does act on the alkali metals at ordinary temp., much the same as does water, with the simultaneous production of flame. 

Environmental Protection. During the reduction of barite and the calcination of Sachtolith and lithopone, sulfur dioxide is liberated. This is removed from the waste gas in a purification stage which is based on the reversible, temperature-dependent solubility of sulfur dioxide in poly glycol. The absorbed sulfur dioxide can be recovered as a liquid product or as a raw material for sulfuric acid. Any soluble barium in the residue from the dissolution of the fused BaS is removed by treatment with... 

When arsine is passed over a heated metal, such as the alkali and alkaline earth metals, zinc or tin, the decomposition of the gas is accelerated and the arsenide of the metal is formed. If platinum is used, the removal of arsenic from the gas is complete.3 The action of sodium or potassium on arsine in liquid ammonia yields 4 the dihydrogen arsenide (MHgAs). Heated alkali hydroxides in the solid form quickly decompose the gas, forming arsenites, and at higher temperatures arsenates and arsenides of the metals.5 The aqueous and alcoholic solutions have no appreciable action.6 When the gas is passed over heated calcium oxide the amount of decomposition is not more than that due to the action of heat alone. Heated barium oxide, however, is converted into a dark brown mixture of barium arsenite and arsenate, hydrogen being liberated.7 The gas is absorbed by soda-lime.8... 

The four-membered azetidine ring remains unaffected by sodium in liquid ammonia, 94 methanolic ammonia, 95 5M barium hydroxide at 100 °C for 24 hours, 87 sodium hydroxide under ester saponification conditions, 87 HC1 at room temperature, 96,97 catalytic hydrogenation under normal conditions, 87,95 and ozonolysisJ87 Correspondingly, as observed for proline, the azetidine-2-carboxylic acid (2) raises no particular difficulties in the synthesis of related peptides. 

Amide. — It has been pointed out before that europium behaves more or less like the alkaline earths and is closely related to strontium and barium. It is found to react with liquid ammonia at —78° C in much the same way as the alkali metals forming a characteristic deep blue solution. Eu(NH2)2 can be isolated [260] from the blue solution. Recent electron paramagnetic studies [261] of solutions of europium in liquid ammonia showed the presence of complex hyperfine lines arising from Eu2+ (8 7/2, g — 1.990 0.002) besides the characteristic single line of the solvated electron (g = 2.0014 0.0002) K The departure of the Eu2+ <7-value from the free electron value is explained as being due to spin-orbit coupling and a slight admixture (3.5%) of the 6P7/2 state. 

Aminoquinoline is obtained from quinoline in 80% yield by treatment with barium amide in liquid ammonia. 

What do a melting ice cube and the reaction of barium hydroxide octahydrate have in common The common feature of these and all other spontaneous processes that absorb heat is an increase in the amount of molecular disorder, or randomness, of the system. The eight water molecules rigidly held in the Ba(OH)2 8 H20 crystal break loose and become free to move about in the aqueous liquid product similarly, the rigidly held H20 molecules in the ice lose their crystalline ordering and move around more freely in liquid water. 

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