Compounds of alkali metals

A review about the Zintl phases has been published by Sevov (2002) from the introduction of this publication we quote a few remarks. It was preliminary observed that the number of Zintl phases has increased many-fold since Zintl s time and that the definition of a Zintl phase has never been very exact often compounds that include non-metals have been considered in this family. The paper by Sevov is mainly dedicated to clearly intermetallic Zintl phases (that is phases containing main group metals, semi-metals or semiconductors only). Attention has therefore been dedicated to compounds of alkali metals with the elements of the 13th, 14th and 15th groups (without B, Al, C, N and P). To this end the following definitions and statements have been considered. 

Recently alkali metals or compounds of alkali metals were found to act as catalysts for reactions, such as isomerization of olefins, dehydrogenation... 

Omloo and Jellinek7 have described the synthesis and characterization of intercalation compounds of alkali metals with the group V layered transition metal dichalcogenides. Typically, these types of intercalation complexes are sensitive to moisture and must be handled in dry argon or nitrogen atmospheres. The alkali metal atoms occupy either octahedral or trigonal prismatic holes between X-M—X slabs. There are two principal means by which these compounds may be prepared. 

The following types of binary compounds of alkali metals (M) and oxygen are known ... 

Substituted quinolylmethanes can be prepared by reaction of the deeply colored compounds of alkali metals with alkyl halides.18... 

An electropositive metal in organic compounds of alkali metals is replaced by a more electropositive one in series of reversible reactions. More electronegative, i. e. more acid, hydrocarbon groups or whole molecules replace those which are less acid [140]. Caesium replaces lithium in ethyllithium. Benzene, which is a stronger acid than ethane, replaces ethyl in ethyllithium. Toluene and H2 are more acid than benzene, and they can therefore replace phenyl in phenylsodium [141, 142],... 

Intercalation compounds of alkali metals. These contain alkali metal ions occupying interstitial sites between fullerene clusters. 

What is the oxidation number of alkaline earth metals in their compounds Of alkali metals (20.1)... 

The heat of hydrolysis can ignite the sohd alkoxides and can present a serions fire hazard. Any contact with water or exposnre of these snbstances to moist air shonld therefore be avoided. Among all the alkoxides, the compounds of alkali metals, especially the potassium derivatives, are the most reactive. Among the alkyl groups, the lower and branched alkyl groups form most reactive derivatives. A few heavy metal alkoxides, such as uranium hexa-fert-butoxide, does not react with water. 

In this experiment you will prepare temporarily hard water study some of the chemical properties of soft, temporarily hard, and permanently hard water and study various processes available for softening hard water. The hardness of different water samples will be tested quantitatively by determining the volume of soap solution that must be added to a given volume of water in order to obtain a lather. Moreover, hard water will be treated by several methods designed to soften it, and the treated water will be titrated with soap solution to test the effectiveness of the methods. A study of the hardness of water, the action of soaps, and methods for softening water will illustrate characteristic chemical reactions and important differences in solubilities of some compounds of alkali metals and the alkaline earth metals. In addition, you will become familiar with a laboratory preparation for and properties of carbon dioxide gas. 

S. Tanuma and K. Kusano, Synthesis of intercalation compounds of alkali metal atoms and a halogen molecule with quasi one dimensional carbon crystal carbolite . Synth. Met., 86,1875-1876 (1997). 

The possibility of using the Sonunerlad method in the preparation of alkali metathioantimonides was tested by performing some calculations in which the direction of the reaction (1) was determined for conq>ounds synthesized byr Sonunerlad and for ternary compounds of alkali metals. 

Dye JL, Andrews CW, Mathews SE (1975) Strategies for the preparation of compounds of alkali metal anions. J Phys Chem 79 3065-3070... 

Arene compounds of V, Cr, and Ru are also formed by reactions of salts of these elements with radical anions of aromatic compounds of alkali metals. 

Standard Enthalpy of Formation of Compounds of Alkali Metals at 25°C (kJ mole )... 

Alkylating agents that have been used include organo compounds of alkali metals, magnesium, aluminum, mercury, and zinc. The following equations illustrate some examples ... 

Addition compounds of alkali-metal hydrides. 25. Rapid reaction of boronic-esters and acids with lithium aluminium hydride. A novel and quantitative synthesis of lithium monoorganylborohydrides, B.Singaram, T.E.Cole and H.C.Brown, Organometalllcs, 1984, 3, 774. 

Fortunately, some stable solid compounds of alkali metals and elements of the IVA group (Si, Ge, Sn, Pb) contain well defined clusters and a study of those alloys may shed light on this problem. Taking the Pb alloys as an example, the equiatomic solid alloys of this element with Na, K, Rb and Cs contain tetrahedral Pb4 clusters surrounded by the alkali atoms. In fact, four alkali atoms cap the faces of each Pb4 tetrahedron forming another... 

Binary compounds of alkali metals and hydrogen react with water to liberate H2(g). The H2 from the reaction of a sample of NaH with an excess of water fiUs a volume of 0.490 L above the water. The temperature of the gas is 35 °C and the total pressure is 758 muiHg. Determine the mass of H2 liberated and the mass of NaH that reacted. 

Omloo WP, Jellinek F (1970) Intercalation compounds of alkali metals with niobium and tantalum dichalcogenides. J Less Common Met 20 121-129... 

This value is consistent with the fact that theoretical models of complexation (e.g. Brown and Sylva, 1987) indicate that the stability of cesium compounds should be less than those of the corresponding compounds of alkali metals that are higher in the periodic table due to the increased size of the cesium ion compared to the alkali metal ions of less mass. 

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