Alkali metals barium

The A2 structure is seen from Table 11-2 to be the preferred one for the alkali metals, barium, the fifth-group metals, and the sixth-group metals it is also observed as one aiiotropic form for titanium, zirconium, iron, and thallium. The factors determining the choice of the A2 structure by certain elements are not known. 

The nohle gases and most metals crystallize in either the hep or the ccp structure as would be expected for neutral atoms. The alkali metals, barium, and a few transition metals crystallize In the body-centered cubic system, though the reasons for this choice are unknown. 

The alkali metals barium (Ba) and uranium (U) are atomic crystalline solids. Their atoms pack in a body-centered cubic arrangement. 

When metallic barium is dissolved in liquid sodium or K/Na alloy in an inert atmosphere of nitrogen, an extensive class of mixed alkali metal-barium... 

Ammonia dissolves alkali metals, barium, calcium and strontium and forms an unstable blue solution. This solution contains the metal ion and free electrons that slowly decompose, release hydrogen and form the metal amide. Compared to water, liquid ammonia is less likely to release protons (H+ ions), is more likely to take up protons (to form NH4+ ions) and is a stronger reducing agent219. 

All hydroxides are insoluble except those of the alkali metals. Barium hydroxide is moderately... 

The alkali metals of Group I are found chiefly as the chlorides (in the earth s crust and in sea water), and also as sulphates and carbonates. Lithium occurs as the aluminatesilicate minerals, spodimene and lepidolite. Of the Group II metals (beryllium to barium) beryllium, the rarest, occurs as the aluminatesilicate, beryl-magnesium is found as the carbonate and (with calcium) as the double carbonate dolomite-, calcium, strontium and barium all occur as carbonates, calcium carbonate being very plentiful as limestone. 

Barium titanate thin films can be deposited on various substances by treating with an aqueous solution containing barium salts and an alkanolamine-modifted titanate such as TYZOR TE (151). In a similar fashion, reaction of a tetraalkyl titanate with an alkah metal hydroxide, such as potassium hydroxide, gives oxyalkoxide derivatives (KTi O(OR) ), which can be further processed to give alkali metal titanate powders, films, and fibers (152—155). The fibers can be used as adsorbents for radioactive metals such as cesium, strontium, and uranium (156). 

I have found that a mixture of citral and acetone, if it is subjected, in the presence of water, for a suffieiently long time to the action of hydrates of alkaline earths or of hydrates of alkali metals, or of other alkaline agents, is eondensed to a ketone of the formula CjjH pO. This substanee, which I term Pseudo-ionone," may be produced lor instance in shaking together for several days equal parts of citral and acetone with a solution of hydrate of barium, and in dissolving the products of this reaction in ether. 

Acid resistance This property is best appreciated when the glass structure is understood. Most enamel frits are complex alkali metal borosilicates and can be visualised as a network of Si04 tetrahedra and BO, triangular configurations containing alkali metals such as lithium, sodium and potassium or alkaline earth metals, especially calcium and barium, in the network interstices. 

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... 

For (203), models indicated that the isomer containing cis-syn-cis hydrogen atoms on the cyclohexane ring should be able to form clam-type complexes, provided the cyclohexane ring is in the flexible or twist conformation. The models suggested that the cavity defined by the ten oxygen donors would be ideal for K+. However, for the potassium and barium thiocyanate complexes, configurations of type (204) do not occur in the solid state. Instead, two molecules of the bis-crown coordinate simultaneously to two alkali metal ions - both these 2 2 complexes have structures of type (205). 

All sulfides (except alkali metals, ammonium, magnesium, calcium, and barium) are insoluble. Aluminum and chromium sulfides are hydrolyzed and precipitate as hydroxides. 

Solubilities of LaCl3-7H20 and of NdCl3-6H20 in acetone/water mixtures have been reported, and compared with those for chlorides of barium and of the alkali metals (323). For these trichlorides, the solubility increases as acetone is added to water up to about 15% acetone, then decreases (LaCl3 and NdCl3 are effectively insoluble in acetone itself). There is also some information, presented only in graphical form, on solubilities of praseodymium trichloride in water-rich methanol, ethanol, and ether mixtures (314), and one fact on yttrium trichloride in a water/ether mixture (264). 

Alkali metal (Group IA) hydroxides (LiOH, NaOH, KOH, RbOH and CsOH) Calcium, strontium, and barium hydroxides... 

Another salt-like group of compounds that have acid-base properties is the hydrides of the alkali metals and calcium, strontium, and barium. These hydrides will react with water to form the hydroxide ion and hydrogen gas ... 

The alkali metal suboxides are well understood in terms of formation, structure, and properties, yet we still face some unsolved problems that will also be addressed in the following. In contrast, the first suboxide of barium came to light only recently [24], and one has to see whether this compound is the tip of another iceberg, as turned out to be the case with the subnitrides of alkaline earth metals. 

Strong bases include the oxides and hydroxides of the alkali metals and also the soluble oxides and hydroxides of the Group 2 metals, such as barium oxide and barium hydroxide. 

Berger and coworkers [17] demonstrated the existence of macrocyclic substances capable of solubilizing alkali metal ions in nonpolar media, and described the formation of sodium and barium salts of a metabolite that had acid properties and was formed in a culture of an unspecified streptomyces. These salts were insoluble in water but dissolved in ether and benzene. The metabolite structure, originally called X 464 [17] and later nigericin [204]... 

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