Potassium and its Compounds

This table lists standard enthalpies of formation AH°, standard third-law entropies S°, standard free energies of formation AG°, and molar heat capacities at constant pressure, Cp, for a variety of substances, all at 25 C (298.15 K) and 1 atm. The table proceeds from the left side to the right side of the periodic table. Binary compounds are listed under the element that occurs to the left in the periodic table, except that binary oxides and hydrides are listed with the other element. Thus, KCl is listed with potassium and its compounds, but CIO2 is listed with chlorine and its compounds. 

The chemistry of potassium and its compounds is very similar to that of the other group 1 elements. Particular ways in which the chemistry of potassium differs from that of sodium can be summarized as follows ... 

Catalysts. Iodine and its compounds ate very active catalysts for many reactions (133). The principal use is in the production of synthetic mbber via Ziegler-Natta catalysts systems. Also, iodine and certain iodides, eg, titanium tetraiodide [7720-83-4], are employed for producing stereospecific polymers, such as polybutadiene mbber (134) about 75% of the iodine consumed in catalysts is assumed to be used for polybutadiene and polyisoprene polymeri2a tion (66) (see RUBBER CHEMICALS). Hydrogen iodide is used as a catalyst in the manufacture of acetic acid from methanol (66). A 99% yield as acetic acid has been reported. In the heat stabiH2ation of nylon suitable for tire cordage, iodine is used in a system involving copper acetate or borate, and potassium iodide (66) (see Tire cords). 

W. A. Hart and O. F. Beumel, Lithium and its compounds, Comprehen.tive Inorganic Chemistry. Vol. 1, Chap. 7, Pergamon Press, Oxford, 1973. T. P. Whaley, Sodium, potassium, rubidium, caesium and francium, ibid.. Chap. 8. 

The thermodynamic behaviour of silver and solubilities of silver and its compounds have been computed in an electrochemical study of silver in potassium hydroxide solutions at high temperature ". ... 

Lithium resembles magnesium, and its compounds show covalent character. Sodium compounds are soluble in water, plentiful, and inexpensive. Potassium compounds are generally less hygroscopic than sodium compounds. 

Underneath this layer of superoxide a layer of oxide KgO is formed. The interaction between potassium and its superoxide is violent and causes the metal to combust the intermediate layer acts as a protection. Contact between both compounds happens when the metal is cut. This slow oxidation is avoided by keeping potassium under anhydrous xylene. It is possible that many dangerous reactions may be in fact due to the exceptional reactivity of the superoxide. 

Reich and Richter found that it is easier to isolate it from the zinc than from the original blende. They reduced indium oxide in a current of hydrogen or illuminating gas and melted the metal under potassium cyanide (44, 45). At the suggestion of Ferdinand Reich, Clemens Winkler made a thorough study of the metal and its compounds (20). 

The microstructure of the polymer varies little with changing reaction conditions 68,104). The effect of temperature is generally small and the alkali metals or their alkyls normally give the same product. Significant differences in microstructure have been noted between potassium and its alkyls (104) and between two different cesium compounds 88) but these effects are not general and their cause is obscure. A more difficult problem exists in that there is poor agreement between the microstructures reported by different authors for a particular initiator and solvent. Tables 3 and 4 include some of the data given for polyisoprene and polybutadiene. Standard infra-red methods were used for the analysis except... 

Atomic Weight.—The chemical properties of caesium indicate its close relationship to the other alkali-metals. It is univalent, forming compounds of the type CsX, its atomic weight and hydrogen equivalent being the same. Its atomic weight is of the order Cs =133 a value conformed by the specific-heat method (Vol. I., p. 88) by the isomorphism of the caesium compounds with those of potassium, ammonium, and rubidium (Vol. I., p. 74) by the correspondence of the properties of the metal and its compounds with the periodic system by the formation of a univalent cation and by the depression of the freezing-point of bismuth chloride and mercuric chloride produced by caesium chloride. 

Ans. The three compounds belong to different nomenclature classes. Potassium in its compounds always forms 1+ ions, and thus there is no need to state 1+ in the name. Copper forms 1+ and 2+ ions, and we need to designate which of these exists in this compound. BrCl is a binary nonmetal-nonmetal compound, using a prefix to denote the number of chlorine atoms. 

Lithium, sodium, and potassium, and their compounds, are of considerable biochemical and industrial importance. " Lithium salts can control manic-depressive psychoses, the Na+/K+ concentration ratio is crucial to nerve impulse transmission, and potassium formulations dominate the plant fertilizer market. Lithium and its salts are used in the production of high-strength and low-density alloys, of lubricating... 

PROP Contains 5% cadmium sebacate, 5% potassium chromate, 1% malachite green, and 16% thiram (FMCHA2 -,D176,80). CONSENSUS REPORTS Cadmium and its compounds, as well as chromium and its compounds, are on the Community Right-To-Know List. 

The Environmental Protection Agency (Cincinnati, OH, USA) reported investigations regarding the health effects of antimony and its compounds. The conclusion of the report is as follows Oral reference dose values (RfDo) were derived for antimony and selected compounds based on the LOAEL (lowest-observed-adverse-effect-level) for antimony of 350/zgkg" day" associated with potassium antimony tartrate (15) in the drinking water of rats for lifetime exposure. Reduced lifespan was observed in both sexes and altered blood biochemical characters in males. The only concentration tested was of 5 ppm antimony. RfDo values for antimony of 24.5/ig dayfor antimony potassium tartrate of 65.5 fig day and for antimony tri-, tetra- and pentoxides of 29.3, 30.9 and 32.5 /igday" respectively, were calculated. It should be noted that orally administered antimony has been inadequately tested for carcinogenicity. 

Conversion of phosphonium salts to salt-free solutions of ylides can also be effected with sodium bis(trimethylsilyl)amide. As it is soluble in many solvents, and easy to handle and to weigh out, sodium bis(trimethylsilyl)amide is preferred to sodamide in liquid ammonia in many cases (equation 11). The corresponding potassium and lithium compounds can also be used. ... 

Of the alkali metals lithium, sodium, potassium, rubidium and cesium, elemental sodium and its compounds are the most important industrially, particularly the mineral and industrial heavy chemicals sodium chloride, sodium carbonate, sodium hydroxide, sodium sulfate etc. In second place is potassium, which is as its salts (chloride, sulfate, nitrate, phosphate) an important component of mineral fertilizers. Lithium and its compounds have a much lower but steadily increasing importance. Cesium and rubidium are only utilized in very small quantities for special applications. 

Sodium is a bright, silvery metal that is soft and has a low density. Like potassium and the other alkali metals, it is too reactive—especially with water—to be found as a pure element in nature. Nevertheless, sodium is the sixth most abundant element in the Earths crust, and its compounds play a vital role in nature. For example, seawater is a natural source of salt (NaCl). When water... 

Nitrosohydroxylaminesulfonates which are less soluble than the sodium salt are obtained by the reaction of sodium sulfite with nitrogen(II) oxide in alkaline medium in the presence of a salt of the desired cation. If the hydroxide of that cation is a strong base, it is used directly. If the hydroxide is a weak base, sodium hydroxide is added. Syntheses of the potassium and ammonium compounds are typical. 

Lithium is one of the most versatile alkali metals. From batteries to lubricants and catalysts to pharmaceuticals, lithium and its compounds find a wide variety of uses. Lithium stands out among the alkali metals for several reasons. It is the lightest alkali metal and the least-dense element that is solid at room temperature and atmospheric pressure. Lithium has the highest melting point of the alkali metals. Its ion (Li+) is the smallest ion in the family. Although less abundant that sodium or potassium, lithium is still relatively inexpensive to obtain. 

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