Alkali and alkaline earth metals hydroxides

Chlorine reacts with alkali and alkaline earth metal hydroxides to form bleaching agents such as NaOQ ... 

Fig. 6. Mean OH stretching frequencies vOH (average of the various unit-cell group modes) of hydroxide ions which do not donate OH- X hydrogen bonds of alkali and alkaline earth metal hydroxides ( ), and on surfaces of solid oxides as A1203 etc. (O) vs mean M-O distances rM Q of the first OMx coordination sphere [22,86] (3556 cm"l, free ion value [1])...

We have seen that the alkali and alkaline earth metal hydroxides [except Be(OH)2l are basic in properties. The following hydroxides are amphoteric Be(OH)2, Al(OH)3, Sn(OH)2, Pb(OH)2, Cr(OH)3, Cu(OH)2, Zn(OH)2, and Cd(OH)2. For example, aluminum hydroxide reacts with both acids and bases ... 

Among the silica-supported alkali and alkaline earth metal hydroxides, CsOH catalyst shows clearly the highest selectivity. 

Structure promoters can act in various ways. In the aromatization of alkanes on Pt catalysts, nonselective dissociative reaction paths that lead to gas and coke formation can be suppressed by alloying with tin. This is attributed to the ensemble effect, which is also responsible for the action of alkali and alkaline earth metal hydroxides on Rh catalysts in the synthesis of methanol from CO/H2 and the hydroformylation of ethylene. It was found that by means of the ensemble effect the promoters block active sites and thus suppress the dissociation of CO. Both reactions require small surface ensembles. As a result, methanol production and insertion of CO into the al-kene are both positively influenced. 

We have seen that the alkali and alkaline earth metal hydroxides [except Be(OH)2] are basic in properties. The following hydroxides are amphoteric Be(OH)2, Al(OH)3,... 

The preparation of soda and lime bleaches (sodium and calcium hypochlorite) is typical of reactions of chlorine with alkalis and alkaline earth metal hydroxides. The hypochlorites formed are powerfiil oxidizing agents. Because of its great affinity for hydrogen, chlorine removes hydrogen from some compounds such as its reaction with hydrogen sulfide to form hydrochloric acid and sulfur. 

E.M.F. studies of electrolyte dissociation. Part 7. Some alkali and alkaline earth metal hydroxides in water. Trans. Faraday Soc., 50, 965-972. 

Heating with the following solids, their fusions, or vapours (a) oxides, peroxides, hydroxides, nitrates, nitrites, sulphides, cyanides, hexacyano-ferrate(III), and hexacyanoferrate(II) of the alkali and alkaline-earth metals (except oxides and hydroxides of calcium and strontium) (b) molten lead, silver, copper, zinc, bismuth, tin, or gold, or mixtures which form these metals upon reduction (c) phosphorus, arsenic, antimony, or silicon, or mixtures which form these elements upon reduction, particularly phosphates, arsenates,... 

A note on good practice The oxides and hydroxides of the alkali and alkaline earth metals are not Bronsted bases the oxide and hydroxide ions they contain are the bases (the cations are spectator ions). However, for convenience, chemists often refer to the compounds themselves as bases. 

This is a quite remarkable result, as the chemoselective hydrogenation of geraniol over a heterogeneous catalyst has rarely been reported. It can be carried out over platinum containing zeolite (9), over Pt/Al203 modified with carboxylic acids (10), over Ni/diatomaceous earth and alkali hydroxides or carbonates (11) or NiRaney and alkali or alkaline earth metal hydroxides (12), yields never exceeding 85%. 

The analysis of tetramethylammonium hydroxide (TMAH) solutions manufactured by SACHEM Inc. of Cleburne, Texas, includes the determination of trace elements. These elements cause less-than-optimum performance of integrated circuit boards manufactured by SACHEM s customers that use these solutions in their processes. Alkali and alkaline earth metals (e.g., Li, Na, K, Mg, Ca, and Ba) can reduce the oxide breakdown voltage of the devices. In addition, transition and heavy metal elements (e.g., Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ag, Au, and Pb) can produce higher dark current. Doping elements (e.g., B, Al, Si, P, As, and Sn) can alter the operating characteristics of the devices. In SACHEM s quality control laboratory, ICP coupled to mass spectrometry is used to simultaneously analyze multiple trace elements in one sample in just 1 to 4 min. This ICP-MS instrument is a state-of-the-art instrument that can provide high throughput and low detection Emits at the parts per thousand level. Trace elemental determination at the parts per thousand level must be performed in a clean room so that trace elemental contamination from airborne particles can be minimized. 

Bauman, J. E. "Alkali- and Alkaline-Earth Metal Oxides and Hydroxides in Water" in "Solubility Data Series ... 

Sulphur is soluble in solutions of the sulphides of the alkali metals, including ammonium, with the formation of yellow solutions of polysulphides.6 The alkali carbonates and the hydroxides of the alkali and alkaline earth metals, in aqueous solution, also dissolve sulphur, producing sulphides or polysulphidcs together with thiosulphates and sulphites. In all probability the ideal equation for hydroxides is ... 

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... 

Now let s consider strong and weak bases. The common strong bases are easy to remember they are the alkali metal and alkaline earth metal hydroxides and oxides, such as calcium oxide (Table J.l). When the oxide dissolves in water, the oxide ions, O2-, accept protons to form hydroxide ions ... 

Water reacts with the alkali metals, the heavier alkaline earth metals (Ca, Sr, Ba, and Ra), and the halogens. With most other elements, water is unreactive at room temperature. Water is reduced to hydrogen by the alkali and alkaline earth metals, which are oxidized to aqueous metal hydroxides ... 

As would be expected, the ionic oxides are formed by the alkali and alkaline earth metals, the most nearly covalent oxides by the nonmetais. The transition metals and many of the other heavy metals form oxides whose bonds are conveniently regarded as being intermediate between the extremes. Many of the oxides react with water to form hydroxides, often the acids and bases of the chemical laboratory. The ionic oxides yield... 

Extremely active metals, such as the alkali and alkaline earth metals, can even react with water to produce hydrogen gas plus the corresponding metal hydroxide. For example ... 

The alkali and alkaline earth metal salts were prepared by neutralizing an aqueous solution of fractionated perfluoro acid with a solution of the hydroxide and evaporating to dryness. 

---