Potassium characteristics

CH2 CH CH0. a colourless, volatile liquid, with characteristic odour. The vapour is poisonous, and intensely irritating to eyes and nose b.p. 53"C. It is prepared by the distillation of a mixture of glycerin, potassium sulphate and potassium hydrogen sulphate. It is manufactured by direct oxidation of propene or cross-condensation of ethanal with meth-anal. 

All the cations of Group I produce a characteristic colour in a flame (lithium, red sodium, yellow potassium, violet rubidium, dark red caesium, blue). The test may be applied quantitatively by atomising an aqueous solution containing Group I cations into a flame and determining the intensities of emission over the visible spectrum with a spectrophotometer Jlame photometry). 

Oxidation, (i) Dissolve 5 g. of potassium dichromate in 20 ml. of dil. H2SO4 in a 100 ml. bolt-head flask. Cool and add 1 ml. of methanol. Fit the flask with a reflux water-condenser and warm gently a vigorous reaction soon occurs and the solution turns green. The characteristic pungent odour of formaldehyde is usually detected at this stage. Continue to heat for 3 minutes and then fit the flask with a knee-tube (Fig. 59, p. 100) and distil off a few ml. Test the distillate with blue litmus-paper to show that it is definitely acid. Then apply Test 3 p. 350) for formic acid. (The reflux-distillation apparatus (Fig. 38, p. 63) can conveniently be used for this test.)... 

Chakactkrisation of Unsaturatkd Aliphatic Hydrocarbons Unlike the saturated hydrocarbons, unsaturated aliphatic hydrocarbons are soluble in concentrated sulphuric acid and exhibit characteristic reactions with dUute potassium permanganate solution and with bromine. Nevertheless, no satisfactory derivatives have yet been developed for these hydrocarbons, and their characterisation must therefore be based upon a determination of their physical properties (boiling point, density and refractive index). The physical properties of a number of selected unsaturated hydrocarbons are collected in Table 111,11. 

Iodine compounds are important in organic chemistry and very useful in medicine. Iodides, and thyroxine which contains iodine, are used internally in medicine, and as a solution of KI and iodine in alcohol is used for external wounds. Potassium iodide finds use in photography. The deep blue color with starch solution is characteristic of the free element. 

Characteristics of common inorganic oxidizers are Hsted in Table 5. In any homologous series, potassium perchlorate-containing propellants bum fastest ammonium nitrate propellants bum slowest (79,80). 

Black Powder. Black powder is mainly used as an igniter for nitrocellulose gun propellant, and to some extent in safety blasting fuse, delay fuses, and in firecrackers. Potassium nitrate black powder (74 wt %, 15.6 wt % carbon, 10.4 wt % sulfur) is used for military appHcations. The slower-burning, less cosdy, and more hygroscopic sodium nitrate black powder (71.0 wt %, 16.5 wt % carbon, 12.5 wt % sulfur) is used industrially. The reaction products of black powder are complex (Table 12) and change with the conditions of initia tion, confinement, and density. The reported thermochemical and performance characteristics vary greatly and depend on the source of material, its physical form, and the method of determination. Typical values are Hsted in Table 13. 

Chemical Properties. Trimethylpentanediol, with a primary and a secondary hydroxyl group, enters into reactions characteristic of other glycols. It reacts readily with various carboxyUc acids and diacids to form esters, diesters, and polyesters (40). Some organometaUic catalysts have proven satisfactory for these reactions, the most versatile being dibutyltin oxide. Several weak bases such as triethanolamine, potassium acetate, lithium acetate, and borax are effective as stabilizers for the glycol during synthesis (41). 

The acid chloride of i i7-nitromethane, CH2=N(C1)0 (mp —43°C, bp 2—3°C), is formed by fusion of nitromethane and picrylpyridinium chloride (36). It is hydroly2ed to nitro some thane, reduces potassium permanganate strongly, and exhibits no reactions characteristic of hydroxamic acids. 

In the days of alchemy and the phlogiston theory, no system of nomenclature that would be considered logical ia the 1990s was possible. Names were not based on composition, but on historical association, eg, Glauber s salt for sodium sulfate decahydrate and Epsom salt for magnesium sulfate physical characteristics, eg, spirit of wiae for ethanol, oil of vitriol for sulfuric acid, butter of antimony for antimony trichloride, Hver of sulfur for potassium sulfide, and cream of tartar for potassium hydrogen tartrate or physiological behavior, eg, caustic soda for sodium hydroxide. Some of these common or trivial names persist, especially ia the nonchemical Hterature. Such names were a necessity at the time they were iatroduced because the concept of molecular stmcture had not been developed, and even elemental composition was incomplete or iadeterminate for many substances. 

Alkali Metal Perchlorates. The anhydrous salts of the Group 1 (lA) or alkah metal perchlorates are isomorphous with one another as well as with ammonium perchlorate. Crystal stmctures have been determined by optical and x-ray methods (38). With the exception of lithium perchlorate, the compounds all exhibit dimorphism when undergoing transitions from rhombic to cubic forms at characteristic temperatures (33,34). Potassium perchlorate [7778-74-7] KCIO, the first such compound discovered, is used in pyrotechnics (qv) and has the highest percentage of oxygen (60.1%). 

Phenol s chemical properties are characterized by the influences of the hydroxyl group and the aromatic ring upon each other. Although the stmcture of phenol is similar to cyclohexanol, phenol is a much stronger acid. Its piC in aqueous solution at 25°C is 9.89 x 10 ° (8). This characteristic allows aqueous hydroxides to convert phenol into their salts. The salts, especially those of sodium and potassium, are converted back into phenol by aqueous mineral acids or carboxyhc acids. 

Potassium bicarbonate is used in foods and medicine. It is approximately twice as effective as NaHC03 in dry-powder fire extinguishers, perhaps because the potassium affects the free-radical mechanism of flame propagation. However, the material does not have good handling characteristics. 

She/fEfe Sensoy, Cooking, and Physica/ Characteristics of Bacon Cured with VayingEeve/s of Sodium Mitrate and Potassium Sorbate, U.S. Dept, of Agriculture, Washington, D.C., July 1979. 

Various methods can be used to analy2e succinic acid and succinic anhydride, depending on the characteristics of the material. Methods generally used to control specifications of pure products include acidimetric titration for total acidity or purity comparison with Pt—Co standard calibrated solutions for color oxidation with potassium permanganate for unsaturated compounds subtracting from the total acidity the anhydride content measured by titration with morpholine for content of free acid in the anhydride atomic absorption or plasma spectroscopy for metals titration with AgNO or BaCl2 for chlorides and sulfates, respectively and comparison of the color of the sulfide solution of the metals with that of a solution with a known Pb content for heavy metals. 

Potassium Heptafluorotantalate. Potassium heptafluoiotantalate [16924-00-8], K TaF, ciystallizes in colodess, rhombic needles. It hydroly2es in Foiling water containing no excess of hydrofluoric acid. The solubility of potassium heptafluorotantalate in hydrofluoric acid decreases from 60 g/100 mL at 100°C to 0.5 g/100 mL at room temperature. The different solubility characteristics of K TaF and K NbOF are the fundamental basis of the Matignac process (16). A phase diagram exists for the system K TaF —NaCl—NaF—KCl (68). Potassium heptafluorotantalate has an LD q value of 2500 mg/kg. The recommended TWA maximum work lace exposure for K TaF in air is 2.5 mg /m (fluoride base) (69). 

PuUy hydroly2ed poly(vinyl alcohol) and iodine form a complex that exhibits a characteristic blue color similar to that formed by iodine and starch (171—173). The color of the complex can be enhanced by the addition of boric acid to the solution consisting of iodine and potassium iodide. This affords a good calorimetric method for the deterrnination of poly(vinyl alcohol). Color intensity of the complex is effected by molecular weight, degree of... 

The elemental and vitamin compositions of some representative yeasts are Hsted in Table 1. The principal carbon and energy sources for yeasts are carbohydrates (usually sugars), alcohols, and organic acids, as weU as a few other specific hydrocarbons. Nitrogen is usually suppHed as ammonia, urea, amino acids or oligopeptides. The main essential mineral elements are phosphoms (suppHed as phosphoric acid), and potassium, with smaller amounts of magnesium and trace amounts of copper, zinc, and iron. These requirements are characteristic of all yeasts. The vitamin requirements, however, differ among species. Eor laboratory and many industrial cultures, a commercial yeast extract contains all the required nutrients (see also Mineral nutrients). 

Potassium hydroxide is the principal electrolyte of choice for the above batteries because of its compatibiUty with the various electrodes, good conductivity, and low freezing point temperature. Potassium hydroxide is a white crystalline substance having a mol wt = 56.10 density = 2.044 g/mL, and mp = 360° C (see Potassium compounds). It is hygroscopic and very soluble in water. The most conductive aqueous solution at 25 °C is at 27% KOH, but the conductivity characteristics are relatively flat over a broad range of concentrations. 

The characteristics for aqueous KOH (97—99) solutions vary somewhat for battery electrolytes when additives are used. Furthermore, potassium hydroxide reacts with many organics and with the carbon dioxide in air to form carbonates. The build-up of carbonates in the electrolyte is to be avoided because carbonates reduce electrolyte conductivity and electrode activity in some cases. 

Glauconite. Glauconite [1317-57-3] (123—126) is a green, dioctahedral, micaceous clay rich in ferric iron and potassium. The generally accepted formula for glauconite is (Na,K)Q yg(Fe " oi o 45 o 65 35) io( )2 Glauconite has many characteristics common to iUite, but much... 

Mica [12001 -26-2]—Cl Pigment White 20, Cl No. 77019. A white powder obtained from the naturally occurring mineral muscovite mica, consisting predominantly of a potassium aluminum siHcate, [1327-44-2] H2KAl2(Si0 2- Mica may be identified and semiquantitatively determined by its characteristic x-ray diffraction pattern and by its optical properties. 

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