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Potassium hydroxide hydrated

Eali-hydrat, n. potassium hydroxide, -hydrat-I6stmg, /. potassium hydroxide solution, potash lye. -kalk, m. potash lime. Kalikodruck, m. calico printing. [Pg.233]

Deliquescence and efflorescence. A substance is said to deliquesce (Latin to become liquid) when it forms a solution or liquid phase upon standing in the air. The essential condition is that the vapour pressure of the saturated solution of the highest hydrate at the ordinary temperature should be less than the partial pressure of the aqueous vapour in the atmosphere. Water will be absorbed by the substance, which gradually liquefies to a saturated solution water vapour will continue to be absorbed by the latter until an unsaturated solution, having the same vapour pressure as the partial pressure of water vapour in the air, is formed. In order that the vapour pressure of the saturated solution may be sufficiently low, the substance must be extremely soluble in water, and it is only such substances (e.g., calcium chloride, zinc chloride and potassium hydroxide) that deliquesce. [Pg.43]

Place 36 -0 g. of redistilled acetophenone, b.p. 201° (Section IV,136), 300 ml. of diethylene glycol, 30 ml. of 90 per cent, hydrazine hydrate and 40 g. of potassium hydroxide pellets in a 500 ml. Claisen flask provided with a reflux condenser and a thermometer dipping into the liquid (compare Fig. Ill, 31, 1). Warm the mixture on a boiling water bath until most of the potassium hydroxide has dissolved and then reflux (free flame) for one hour. Arrange the apparatus for distillation and distil until the temperature in the liquid rises to 175° (1) keep the distillate (ca. 50 ml.). Replace the reflux condenser in the flask and continue the refluxing for 3 hours. [Pg.516]

The independent preparation of potassium phthabmide (from a solution of phthalimide in absolute ethanol and potassium hydroxide in 75 per cent, ethanol) may be avoided in many cases by boiling phthalimide with the halide in the presence of anhydrous potassium carbonate. The N-substituted phthalimide (I) is frequently cleav with difficulty this is often facilitated by reaction with hydrazine hydrate to give an intermediate product, which is easily decomposed by hydrochloric acid to 3deld the insoluble hydrazide of phthaUc acid (II) and the primary amine (III) ... [Pg.560]

Benzylatnine. Warm an alcoholic suspension of 118-5 g. of finely-powdered benzyl phthalimide with 25 g. of 100 per cent, hydrazine hydrate (CAUTION corrosive liquid) a white, gelatinous precipitate is produced rapidly. Decompose the latter (when its formation appears complete) by heating with excess of hydrochloric acid on a steam bath. Collect the phthalyl hydrazide which separates by suction filtration, and wash it with a little water. Concentrate the filtrate by distillation to remove alcohol, cool, filter from the small amount of precipitated phthalyl hydrazide, render alkaline with excess of sodium hydroxide solution, and extract the liberated benzylamine with ether. Dry the ethereal solution with potassium hydroxide pellets, remove the solvent (compare Fig. //, 13, 4) on a water bath and finally distil the residue. Collect the benzylamine at 185-187° the 3ueld is 50 g. [Pg.569]

Hydrated Stannic Oxide. Hydrated stannic oxide of variable water content is obtained by the hydrolysis of stannates. Acidification of a sodium stannate solution precipitates the hydrate as a flocculent white mass. The colloidal solution, which is obtained by washing the mass free of water-soluble ions and peptization with potassium hydroxide, is stable below 50°C and forms the basis for the patented Tin Sol process for replenishing tin in staimate tin-plating baths. A similar type of solution (Staimasol A and B) is prepared by the direct electrolysis of concentrated potassium staimate solutions (26). [Pg.66]

Vinyl chloride reacts with sulfides, thiols, alcohols, and oximes in basic media. Reaction with hydrated sodium sulfide [1313-82-2] in a mixture of dimethyl sulfoxide [67-68-5] (DMSO) and potassium hydroxide [1310-58-3], KOH, yields divinyl sulfide [627-51-0] and sulfur-containing heterocycles (27). Various vinyl sulfides can be obtained by reacting vinyl chloride with thiols in the presence of base (28). Vinyl ethers are produced in similar fashion, from the reaction of vinyl chloride with alcohols in the presence of a strong base (29,30). A variety of pyrroles and indoles have also been prepared by reacting vinyl chloride with different ketoximes or oximes in a mixture of DMSO and KOH (31). [Pg.414]

Chloroform and water at 0°C form six-sided crystals of a hydrate, CHCl I8H2O [67922-19-41which decompose at 1.6°C. Chloroform does not decompose appreciably when in prolonged contact with water at ordinary temperature and in the absence of air. However, on prolonged heating with water at 225°C, decomposition to formic acid, carbon monoxide, and hydrogen chloride occurs. A similar hydrolysis takes place when chloroform is decomposed at elevated temperature by potassium hydroxide. [Pg.524]

Potassium hydroxide gives better results than does sodium hydroxide since, if the latter is used, the large amount of hydrated sodium sulfate which separates from the solution prevents efficient cooling. [Pg.61]

Chloroquinoline (401) reacts well with potassium fluoride in dimethylsulfone while its monocyclic analog 2-chloropyridine does not. Greater reactivity of derivatives of the bicyclic azine is evident also from the kinetic data (Table X, p. 336). 2-Chloroquinoline is alkoxylated by brief heating with methanolic methoxide or ethano-lic potassium hydroxide and is converted in very high yield into the thioether by trituration with thiocresol (20°, few hrs). It also reacts with active methylene carbanions (45-100% yield). The less reactive 3-halogen can be replaced under vigorous conditions (160°, aqueous ammonia-copper sulfate), as used for 3-bromoquino-line or its iV-oxide. 4-Chloroquinoline (406) is substituted by alcoholic hydrazine hydrate (80°, < 8 hr, 20% yield) and by methanolic methoxide (140°, < 3 hr, > 90% yield). This apparent reversal of the relative reactivity does not appear to be reliable in the face of the kinetic data (Tables X and XI, pp. 336 and 338) and the other qualitative comparisons presented here. [Pg.364]

The carbonyl compound to be reduced (0.1 mole) is placed in a 250-ml round-bottom flask with 13.5 g of potassium hydroxide, 10 ml of 85% hydrazine hydrate, and 1(X) ml of diethylene glycol. A reflux condenser is attached and the mixture is heated to reflux for I hour (mantle). After refluxing 1 hour, the condenser is removed and a thermometer is immersed in the reaction mixture while slow boiling is continued to remove water. When the pot temperature has reached 200°, the condenser is replaced and refluxing is continued for an additional 3 hours. The mixture is then cooled, acidified with concentrated hydrochloric acid, and extracted with benzene. The benzene solution is dried, and the benzene is evaporated to afford the crude product, which is purified by recrystallization or distillation. [Pg.55]

Kalium-hydrat, n. potassium hydroxide, -hy-drid, n. potassium hydride (KH). -hydroxyd, n. potassium hydroxide, -hydriir, n. potassium subhydride (IC2H or K4H2). -iridi-chlorid, n. potassium eh loroiridate. -jodat, n. potassium iodate. [Pg.233]

Acetyl-l 2-ketochenodeoxycholic acid Hydrazine hydrate Potassium hydroxide... [Pg.294]

To 1,400 ml of an approximately 50% water/triglycol solution of the potassium salt of cheno-deoxycholic acid, obtained by the Wolff-Kishner reduction (using hydrazine hydrate and potassium hydroxide) from 50 g of 7-acetyl-12-ketochenodeoxycholic acid, 220 ml of dilute hydrochloric acid is added to bring the pH to 2. The solution is stirred and the crude cheno-deoxycholic acid precipitates. The precipitate is recovered and dried to constant weight at about 60°C. About 36 g of the crude chenodeoxycholic acid, melting in the range of 126°-129°C, is obtained. [Pg.294]

A slant of S. antibioticus ATCC 11891 was cultivated on agar under controlled conditions in order to develop spores for the purpose of inoculating a nutrient medium having the following composition 20 g Cerelose (dextrose hydrate), 15 g soybean meal, 5 g distillers solubles, 10 g cornmeal, and tap water, in a sufficient amount for a 1,000-ml solution, adjusted to pH 7.0 to 7.2 with potassium hydroxide. [Pg.1111]

Reaction (II) could be the neutralization of acetic acid by potassium hydroxide, yielding potassium acetate which can be isolated in the crystalline state. On dissolution in water the K+ cation is only hydrated in solution but does not participate in a protolytic reaction. In this way, the weak base CH3COO is quantitatively introduced into solution in the absence of an equilibrium amount of the conjugate weak acid CH3COOH. Thus... [Pg.64]

The use of mesitoic acid esters has again been successfully employed by Burrows and Topping (1975) in the elucidation of intramolecular carbon acid participation. Under basic aqueous conditions, 2-acetylphenyl mesitoate [41] hydrolyses to yield mesitoic acid and 2-hydroxyacetophenone, reacting with intramolecular catalysis via the monoanion of the ketonic hydrate (see p. 192). However, in 47.5% aqueous ethanol containing potassium hydroxide, the reaction products from l-acetyl-2-naphthyl mesitoate [45] were found... [Pg.197]


See other pages where Potassium hydroxide hydrated is mentioned: [Pg.325]    [Pg.43]    [Pg.274]    [Pg.146]    [Pg.146]    [Pg.25]    [Pg.526]    [Pg.103]    [Pg.891]    [Pg.892]    [Pg.103]    [Pg.498]    [Pg.571]    [Pg.151]    [Pg.1505]    [Pg.36]    [Pg.177]    [Pg.24]    [Pg.53]    [Pg.510]    [Pg.264]    [Pg.181]    [Pg.675]    [Pg.1925]    [Pg.49]    [Pg.368]    [Pg.500]   
See also in sourсe #XX -- [ Pg.335 , Pg.624 ]

See also in sourсe #XX -- [ Pg.335 ]




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Hydration hydroxide

Hydroxide hydrate

Hydroxides Potassium hydroxide

Potassium hydrate

Potassium hydrate hydroxide

Potassium hydrate hydroxide

Potassium hydroxide

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