Chlorine, preparation

Chlorine prepared from manganese dioxide and pure HC1 was liquefied and the dry gas evolved from the liquid was admitted to the dry phosphorus in a vacuum. In this ease phosphorus pentachloride was formed in considerable quantity and was removed only by several distillations. It could not be inferred with such confidence that the trichloride was free from pentachloride as that the tribromide was free from bromine. The trichloride was decomposed and oxidised in the manner already described. In the subsequent estimation of the silver chloride less difficulty was experienced in freeing this from occluded chloride, but more difficulty in determining accurately the amount of silver chloride remaining in solution. It was found possible, however, to diminish the solubility by adding an excess of silver nitrate solution and partly washing the precipitated chloride with this solution. 

Starting with a mixture of hydrogen and chlorine—-prepared by the electrolysis of hydrochloric acid in darkness—no movement was observed for 600.seconds after the commencement of exposure, and after that the time occupied by the liquid in moving over the 1st, 2nd, 3rd, 4th, and 5th divisions of the scale was respectively 480,165, 130, 95, and 93 seconds, and thereafter it moved regularly at the same rate. These results are graphed in Fig. 6, as average velocities per second. Starting from the moment the mixture is illumi-... 

Hepatovirucidal substances such as aldehyde derivatives, chlorine preparations (as long as chlorine is released at a low pH), glyoxal, n-propanol and iodine have proved to be effective. Virus destruction is also achieved by heating (e.g. 100°C >10 minutes, or hot air 180°C >2 hours, or steam 120°C >20 minutes at 1 bar). Just as effective in inactivating a virus is the boiling of instruments or equipment in a soda solution for 15 minutes. As far as possible,... 

There are no particular measures for inactivating HCV, except for the same disinfecting procedures as applied for viral hepatitis B. Emphasis is thus placed on formalin, aldehyde derivatives and chlorine preparations as well as heating (e.g. 60°C for 10 hours), (s. p. 423)... 

W. Cruickshank made a mixture of 2 vols. of moist chlorine (prepared by the action of hydrochloric acid on potassium chlorate) and i vol. of hydrogen in a bottle. There was no immediate action but after 24 hours the gases had... 

How are elementary hydrogen, nitrogen, phosphorus, oxygen, and chlorine prepared commercially ... 

To compensate for the salt error, calibrate the method as described in Section 11.2.8.3 using the artificial seawater. To ISmL aliquots add 0.5,1.0,1.5 and 2.0 mL of the fluoride working standard and 8.0 mL of the alizarin reagent. For seawater samples with different chlorinities, prepare individual calibration curves with chlorinities of 0,5,10,15 and 20 %o. 

It is prepared by the direct chlorination of toluene in the presence of PClj. It is purified by fractionation from the unchanged toluene and the higher chlorinated products. It is used for benzylating amines and for preparing benzyl alcohol. 

It is prepared by fully chlorinating toluene. When heated with water at 100°C, or with lime, benzoic acid is obtained, benzoyl The group PhC(O)-. 

Other chlorinated naphthalenes. The other monochloronaphthalene (2-), the ten theoretically possible dichloronaphthalenes, and the fourteen trichloronaphthalenes have all been prepared, generally from the corresponding amino-derivatives by diazotization and treatment with CuCl. They are of little industrial importance. 

CH2CI2. A colourless liquid with a chloroform-like odour b.p. 4I°C. Prepared by heating chloroform with zinc, alcohol and hydrochloric acid manufactured by the direct chlorination of methane. Decomposed by water at 200°C to give methanoic and hydrochloric acids. Largely used as a solvent for polar and non-polar substances, particularly for paint removal (30%), dissolving cellulose acetate and degreasing (10%). It is more stable than carbon tetrachloride or chloroform especially towards moisture or alkali. It is somewhat toxic. U.S. production 1981 280000 tonnes. 

Glycerol -dichlorohydrin, 2.3-dichloro-propanol, CH2CI CHC1 CH2 0H. Colourless liquid, b.p. 182 C. Prepared by the chlorination of propenyl alcohol. Oxidized by nitric acid to 1,2-dichloropropionic acid. Reacts with NaOH to give epichlorohydrin. 

Prepared by condensing p-chlorophenol with phlhalic anhydride in sulphuric acid solution in the presence of boric acid. The chlorine atom is replaced by hydroxyl during the condensation. It can also be prepared by oxidation of anthraquinone or 1-hydroxyanthraquinone by means of sulphuric acid in the presence of mercury(ll) sulphate and boric acid. 

M.p. 255-257 C. Prepared by the direct chlorination of phlhalic anhydride in 50-60% oleum in the presence of iodine, the temperature being raised from 50-200 C as the reaction proceeds. 

The values of AH indicate that it is extremely unlikely that MgCljIs) can be prepared under any conditions, but both MgCl(s) and MgCl2(s) appear to be energetically stable with respect to magnesium and chlorine. 

Both boron and aluminium chlorides can be prepared by the direct combination of the elements. Boron trichloride can also be prepared by passing chlorine gas over a strongly heated mixture of boron trioxide and carbon. Like boron trifluoride, this is a covalent compound and a gas at ordinary temperature and pressure (boiling point 285 K). It reacts vigorously with water, the mechanism probably involving initial co-ordination of a water molecule (p, 152). and hydrochloric acid is obtained ... 

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