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Alkali with water

To prepare the catalyst under methylcyclohexane (Note 9), the catalyst, which has been prepared as above and washed free of alkali with water, but to which no alcohol has been added, is covered with 1 1. of methylcyclohexane which is distilled from an oil bath until all the water has been codistilled with the hydrocarbon, more of the methylcyclohexane being added from time to time so that the nickel always remains covered. When the catalyst is free from water it becomes freely suspended in the liquid. [Pg.16]

Then the steam is turned off and the system is washed free of alkali with water. [Pg.128]

CCls CHO. A colourless oily liquid with a pungent odour b.p. 98°C. Manut actured by the action of chlorine on ethanol it is also made by the chlorination of ethanal. When allowed to stand, it changes slowly to a white solid. Addition compounds are formed with water see chloral hydrate), ammonia, sodium hydrogen sulphite, alcohols, and some amines and amides. Oxidized by nitric acid to tri-chloroethanoic acid. Decomposed by alkalis to chloroform and a methanoate a convenient method of obtaining pure CHCI3. It is used for the manufacture of DDT. It is also used as a hypnotic. [Pg.91]

Colourless liquid with a characteristic ammo-niacal smell m.p. 9 C, b.p. 106°C. Miscible with water. It is present in pepper as the alkaloid piperine from which it can be obtained by healing with alkali. It can also be prepared by the reduction of pyridine, either electrolytically or by other means. Piperidine is a strong base, behaving like the aliphatic amines. [Pg.315]

Silicon and germanium readily react with even very dilute solutions of caustic alkali. Silicon is so sensitive to attack that it will dissolve when boiled with water which has been in contact with glass ... [Pg.171]

Silanes are very sensitive to attack by alkalis and will even react with water made alkaline by contact with glass this reaction is in marked contrast to the reactions shown by alkanes. Unlike alkanes, silanes are found to have marked reducing properties and will reduce, for example, potassium manganate(VII) to manganeseflV) oxide, and iron(III) to iron(II). [Pg.176]

Sulphur dioxide is an acidic oxide and dissolves readily in water, and in alkalis with which it forms salts ... [Pg.290]

Dissolve I ml. of benzaldehyde and 0-4 ml. of pure acetone in 10 ml. of methylated spirit contained in a conical flask or widemouthed bottle of about 50 ml. capacity. Dilute 2 ml. of 10% aqueous sodium hydroxide solution with 8 ml. of water, and add this dilute alkali solution to the former solution. Shake the mixture vigorously in the securely corked flask for about 10 minutes (releasing the pressure from time to time if necessary) and then allow to stand for 30 minutes, with occasional shaking finally cool in ice-water for a few minutes. During the shaking, the dibenzal -acetone separates at first as a fine emulsion which then rapidly forms pale yellow crystals. Filter at the pump, wash well with water to eliminate traces of alkali, and then drain thoroughly. Recrystallise from hot methylated or rectified spirit. The dibenzal-acetone is obtained as pale yellow crystals, m.p. 112 yield, o 6 g. [Pg.231]

Acetylation. Proceed as in 2 (p. 373). Pour the final acetylation mixture into 10 ml. of water, and add 10% NaOH solution, with stirring, until no more anilide is precipitated (acetyl-monoethylaniline is very soluble even in dil. acetic acid acetyUdiphenylamine readily separates without the addition of alkali). Filter, wash with water and recrystallise. [Pg.376]

The acetylations may alternatively be performed in 100 ml. conical flasks, and the contents after dilution and hydrolysis with water can then be carefully washed into 250 ml. beakers for the titration with alkali. The calculation is precisely similar to that of the first method. Excellent results are r>btalned. [Pg.454]

Most aromatic acid chlorides impart a strongly acid reaction when shaken with water (compare Section 111,88). All are completely hydrolysed by boiling with solutions of caustic alkalis and yield no product volatile from the alkaline solution (compare Eaters, Sections 111,106 and IV, 183). They may be distinguished from acids by their facile reactions with alcohols (compare Section 111,27), phenols (compare Section IV,114), and amines (compare Sections 111,123 and IV.lOO). [Pg.795]

Methyl p-toluenesulphonate. This, and other alkyl esters, may be prepared in a somewhat similar manner to the n-butyl ester with good results. Use 500 g. (632 ml.) of methyl alcohol contained in a 1 litre three-necked or bolt-head flask. Add 500 g. of powdered pure p-toluene-sulphonyl chloride with mechanical stirring. Add from a separatory funnel 420 g. of 25 per cent, sodium hydroxide solution drop by drop maintain the temperature of the mixture at 23-27°. When all the alkali has been introduced, test the mixture with litmus if it is not alkaline, add more alkali until the mixture is neutral. Allow to stand for several hours the lower layer is the eater and the upper one consists of alcohol. Separate the ester, wash it with water, then with 4 per cent, sodium carbonate solution and finally with water. Dry over a little anhydrous magnesium sulphate, and distil under reduced pressure. Collect the methyl p-toluenesulphonate at 161°/10 mm. this solidifies on cooling and melts at 28°. The yield is 440 g. [Pg.825]

Method A. Cool a solution of the nitrate-free dichloride, prepared from or equivalent to 5 0 g. of palladium or platinum, in 50 ml. of water and 5 ml. of concentrated hydrochloric acid in a freezing mixture, and treat it with 50 ml. of formahn (40 per cent, formaldehyde) and 11 g. of the carrier (charcoal or asbestos). Stir the mixture mechanically and add a solution of 50 g. of potassium hydroxide in 50 ml. of water, keeping the temperature below 5°. When the addition is complete, raise the temperature to 60° for 15 minutes. Wash the catalyst thoroughly by decantation with water and finally with dilute acetic acid, collect on a suction filter, and wash with hot water until free from chloride or alkali. Dry at 100° and store in a desiccator. [Pg.948]

To determine the exact diazomethane content, allow an aliquot portion of the ethereal diazomethane solution to react with an accurately weighed amount (say, about 1 g.) of A. R. benzoic acid in 60 ml. of anhydrous ether. The solution should be completely decolourised, thus showing that the benzoic acid is present in excess. Dilute the solution with water and titrate the excess of benzoic acid with standard 0 IN alkali using phenolphthalein as indicator. [Pg.972]

Esters of sulphuric acid. These compounds are generally water insoluble liquids and are saponified by boiling with water or dilute alkali to the corresponding alcohols and sulphuric acid ... [Pg.1078]

Alkalis on the skin. Wash immediately with a large volume of water, then with 1 per cent, acetic acid, and finally with water. For a serious burn, follow this treatment by applying a disinfectant, drying the skin and covering with acriflavine jelly. [Pg.1131]

Lithium is presently being recovered from brines of Searles Lake, in California, and from those in Nevada. Large deposits of quadramene are found in North Carolina. The metal is produced electrolytically from the fused chloride. Lithium is silvery in appearance, much like Na and K, other members of the alkali metal series. It reacts with water, but not as vigorously as sodium. Lithium imparts a beautiful crimson color to a flame, but when the metal burns strongly, the flame is a dazzling white. [Pg.9]

Nitramine, picrylmethylnitramine, 2,4,6-trinitrophenylmethyl nitramine (indicator) dissolve 0.1 g in 60 mL alcohol and dilute with water to 100 mL pH range colorless 10.8-13.0 red-brown the solution should be kept in the dark as nitramine is unstable on boiling with alkali it decomposes quickly. Fresh solutions should be prepared every few months. [Pg.1194]

Even small spills and leaks (<0.45 kg) require extreme caution. Unless the spill is contained in a fume hood, do not remain in or enter the area unless equipped with full protective equipment and clothing. Self-contained breathing apparatus should be used if the odor of acrolein or eye irritation is sensed. Small spills may be covered with absorbant, treated with aqueous alkalies, and flushed with water. [Pg.129]

Liquid metals, however, present several disadvantages. Their weights must be considered with regard to equipment design. Additionally, Hquid metals are difficult to contain and special pumps must be used for system safety. Alkali metals react violentiy with water and bum ia air. Liquid metals also may become radioactive whea used for cooling auclear reactors (qv). [Pg.505]

The stability of the alkali metal ozonides increases from Li to Cs alkaline-earth ozonides exhibit a similar stability pattern. Reaction of metal ozonides with water proceeds through the intermediate formation of hydroxyl radicals. [Pg.492]

Removal of Free Fatf Fields. Alkali treatment of the oil is accompHshed by the use of caustic soda solutions to neutralize the excess free fatty acids. Because castor oil readily forms emulsions with water and/or alkaline solutions, special techniques have been developed to neutralize the acids. A continuous counter-current process was developed using a stationary contact reactor (15). Treatment in the presence of a solvent is also utilized (16). [Pg.152]

Properties. HydroxyethjIceUulose [9004-62-0] (HEC), is a nonionic polymer. Low hydroxyethyl substitutions (MS = 0.05-0.5) yield products that are soluble only in aqueous alkali. Higher substitutions (MS > 1.5) produce water-soluble HEC. The bulk of commercial HEC falls into the latter category. Water-soluble HEC is widely used because of its broad compatibiUty with cations and the lack of a solution gel or precipitation point in water up to the boiling point. The MS of commercial HEC varies from about 1.8 to 3.5. The products are soluble in hot and cold water but insoluble in hydrocarbon solvents. HEC swells or becomes pardy to mosdy soluble in select polar solvents, usually those that are miscible with water. [Pg.274]


See other pages where Alkali with water is mentioned: [Pg.147]    [Pg.135]    [Pg.520]    [Pg.275]    [Pg.271]    [Pg.76]    [Pg.703]    [Pg.160]    [Pg.871]    [Pg.147]    [Pg.135]    [Pg.520]    [Pg.275]    [Pg.271]    [Pg.76]    [Pg.703]    [Pg.160]    [Pg.871]    [Pg.75]    [Pg.98]    [Pg.135]    [Pg.163]    [Pg.167]    [Pg.241]    [Pg.248]    [Pg.324]    [Pg.362]    [Pg.176]    [Pg.299]    [Pg.499]    [Pg.668]    [Pg.865]    [Pg.894]    [Pg.976]    [Pg.72]    [Pg.84]   
See also in sourсe #XX -- [ Pg.776 ]




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