Carbon disulphide and acetone

Mercury di-o-nitrophenyl occurs in pale yellow needles, M.pt. 206 to 207° C., easily soluble in pyridine, hot acetone, and carbon disulphide, sparingly in carbon tetrachloride. Yield 92 per cent. When boiled with concentrated hydrochloric acid nitrobenzene is split off. 

It is sparingly soluble in alcohol and acetone, insoluble in ether, chloroform and carbon disulphide.8 Alkalis and ammonia in aqueous solution readily dissolve it. It is also soluble in a solution of hydriodie acid. 

The solvents more generally used are oil of turpentine, pinewood oil, methyl, ethyl or amyl alcohol, amyl acetate, acetone, ether, carbon disulphide, carbon tetrachloride, chloro-derivatives of ethane and ethylene, chlorohydrins, light mineral oils, light oils from tar, from resin or from shale, and camphor oil. 

Triphenylarsine hydroxybromide, (CgH6)3As(OH)Br, is produced by the decomposition of the corresponding cyanobromide by moisture. It forms glistening crystals, M.pt. 166° C., soluble in alcohol, chloroform, and acetone, sparingly soluble in water and carbon disulphide, insoluble in ether and petroleum ether. When heated in a... 

This product is best obtained by heating dehydroquininc with about five times its weight of arsenic trichloride in an oil-bath at 130" to 135" for three hours, in the absence of a solvent. It may also be prepared by digesting the previous compound with aqueous ammonium carbonate. It darkens at 199° to 200° C., sinters at about 204° C., and melts at 207 to 209° C. it is easily soluble in alcohols and pyridine, very sparingly soluble in chloroform and acetone, and insoluble in ether, ethyl acetate, aromatic hydrocarbons, and carbon disulphide. Its salts arc not crystalline. The fact that it forms a benzoyl derivative shows the presence of a free hydroxyl group, and consequently the attachment of the arsenic to the vinyl group. 

The following pairs have neither a maximum nor a minimum vapour pressure water and acetone, ethyl alcohol and acetone, ethyl alcohol and carbon disulphide, acetic acid and benzene, ether and benzene, etc. The following pairs have rectihnear vapour pressure curves benzene and chlorbenzene, benzene and brombenzene, toluene and chlorbenzene, ethylene bromide and propylene bromide. Thus, for very similar pairs, the vapour pressure curve is a straight line. 

Mercuri-bis-p-bromodimethylaniline.—The acetate, 27 6 grams, is mixed with 23 grams of potassium iodide in 200 c.c. of alcohol, and the mixture heated under reflux for eight hours. The precipitate is filtered and extracted with cold benzene to remove impurities. Yield 15-5 grams, 86 per cent. Four crystallisations from benzene give fine, white needles, M.pt. 123° C., readily soluble in cold benzene, toluene, ether, acetone, or carbon disulphide. Smaller yields of this compound are also obtained from the above acetate by the action of sodium thiosulphate or potassium sulphide. 

This should be white and as transparent as possible. It should have no taste or smell. It must be free from mechanical impurities and acidity, and must dissolve completely in acetone or carbon disulphide.. On ignition it should give ver> little ash. The melting point is not very definite. It is generally specified for the special purpose for which the paraffin wax is required. The determination of the setting point is sometimes preferred. 

Tetraethylphosphonium antimonyl d-tartrate is obtained in aqueous solution when equivalents of tetraethylphosphonium iodide and silver antimonyl d-tartrate are mixed in solution. The solution is filtered, and the tartrate isolated in quantitative yield by evaporating off the solvent. It forms a white powder, very soluble m water, but insoluble in ether, acetone, benzene, carbon disulphide, or chloroform. By a similar process tetra-n-propylphosphonium antimonyl d-ta f irate is obtained. 

Campbell, A. N. Kartzmark, E. M. Thermodynamic and other properties of methemol + acetone, caibon disulphide + acetone, carbon disulphide -1- methanol, and carbon disulphide + methtmol + acetone J. Chem. Thermodyn. 1973,5,163-172... 

Like bromine, iodine is soluble in organic solvents, for example chloroform, which can be used to extract it from an aqueous solution. The iodine imparts a characteristic purple colour to the organic layer this is used as a test for iodine (p. 349). NB Brown solutions are formed when iodine dissolves in ether, alcohol, and acetone. In chloroform and benzene a purple solution is formed, whilst a violet solution is produced in carbon disulphide and some hydrocarbons. These colours arise due to charge transfer (p. 60) to and from the iodine and the solvent organic molecules. 

The inflammable solvents most frequently used for reaction media, extraction or recrystallisation are diethyl ether, petroleum ether (b.p. 40-60° and higher ranges), carbon disulphide, acetone, methyl and ethyl alcohols, di-Mo-propyl ether, benzene, and toluene. Special precautions must be taken in handling these (and other equivalent) solvents if the danger of Are is to be more or less completely eliminated. It is advisable to have, if possible, a special bench in the laboratory devoted entirely to the recovery or distillation of these solvents no flames are permitted on this bench. 

Selection of solvents. The choice of solvent will naturally depend in the first place upon the solubility relations of the substance. If this is already in solution, for example, as an extract, it is usually evaporated to dryness under reduced pressure and then dissolved in a suitable medium the solution must be dilute since crystallisation in the column must be avoided. The solvents generally employed possess boiling points between 40° and 85°. The most widely used medium is light petroleum (b.p. not above 80°) others are cycZohexane, carbon disulphide, benzene, chloroform, carbon tetrachloride, methylene chloride, ethyl acetate, ethyl alcohol, acetone, ether and acetic acid. 

Quinoline, when exposed to light, forms first a yellow liquid, and slowly a hrown liquid. It is only slightly soluble in water hut dissolves readily in many organic solvents. Isoquinoline crystallizes to platelets and is sparingly soluble in water but dissolves well in ethanol, acetone, diethyl ether, carbon disulphide and other common organic solvents. It is also soluble in dilute... 

Similarly with the raising of the b.p. in violet or reddish-violet soln. of iodine in benzophenone, carbon disulphide, ethyl chloride, chloroform, carbon tetrachloride, ethylene chloride or benzene or in brown soln. of ethyl alcohol, methyl alcohol, thymol, ethyl ether, methylal, or acetone. The values for the last three solvents were rather low, presumably because of the chemical action of solute on solvent. High values with benzene are attributed to the formation of a solid soln. of solvent and solid. Confirmatory results were found by J. Hertz with naphthalene, and by E. Beckmann and P. Wantig with pyridine. The results by I. von Ostromisslensky (o-nitrotoluene), by G. Kriiss and E. Thiele (glacial acetic acid), and by H. Gautier and G. Charpy indicate polymerization, but they are not considered to be reliable. 

Compounds with low flash points (below room temperature). Examples are acetaldehyde, acetone, acetonitrile, benzene, carbon disulphide, cyclohexane, diethyl ether, ethyl acetate and n-hexane. 

Great care is necessary in the use of ether, light petroleum, carbon disulphide, acetone, alcohol, benzene, etc., as the vapours of these are highly inflammable. They should always be distilled from a water bath and be collected in the apparatus shown on p. 20. Special care is necessary with carbon disulphide, as its vapour inflames in contact with a warm surface, even in the absence of a flame. 

The chief impurities in commercial ether are alcohol and water, with traces of aldehyde, methyl alcohol, acetone, due to it being made from methylated spirit. It may be purified as above. The presence of alcohol may be proved by shaking with a spirit soluble dye, e.g., aniline violet. If alcohol is present a blue solution is obtained. Water is detected by the cloudiness formed on mixing with carbon disulphide. 

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