Hydrochloric acid , solid-state

Chemical Designations - Synonyms Anhydrous Aluminum Chloride Chemical Formula AICI3 Observable Characteristics - Physical State (as normally shipped) Solid Color Orange to yellow through gray to white Odor Like hydrogen chloride like hydrochloric acid. 

A 1.5 to 2 M solution of methylsulfinyl carbanion in dimethyl sulfoxide is prepared under nitrogen as above from sodium hydride and dry dimethyl sulfoxide. An equal volume of dry tetrahydrofuran is added and the solution is cooled in an ice bath during the addition, with stirring, of the ester (0.5 equivalent for each 1 equivalent of carbanion neat if liquid, or dissolved in dry tetrahydrofuran if solid) over a period of several minutes. The ice bath is removed and stirring is continued for 30 minutes. The reaction mixture is then poured into three times its volume of water, acidified with aqueous hydrochloric acid to a pH of 3-4 (pH paper), and thoroughly extracted with chloroform. The combined extracts are washed three times with water, dried over anhydrous sodium sulfate, and evaporated to yield the jS-ketosulfoxide as a white or pale yellow crystalline solid. The crude product is triturated with cold ether or isopropyl ether and filtered to give the product in a good state of purity. 

According to EPA (1974), pesticides such as endosulfan should be destroyed at high temperature in an approved incinerator with a hydrochloric acid scrubber, if available. Any sludges or solid residues generated from this process are to be disposed of in a manner approved by all applicable federal, state, and local pollution control requirements. EPA strongly recommends that if incineration of excess pesticides is not possible, organic pesticides should be buried in a designated landfill site. 

In a i-l. three-necked flask fitted with a fetirrer and thermometer are placed 93 g. (0.5 mole) of dodecanol (Note 1) and 158 g. (2 moles) of pyridine. The flask is surrounded by a water bath sufficiently cold to lower the temperature of the mixture to io°. At this temperature 105 g. (0.55 mole) of />-toluenesul-fonyl chloride is added in portions over a twenty- to thirty-minute period, or at such a rate that the temperature does not exceed 20° at any time. The mixture is then stirred for three hours at a temperature below 20°, after which it is diluted with 300 cc. of hydrochloric acid (sp.gr. 1.19) in 11. of ice water. The ester which crystallizes is collected on a chilled Buchner funnel and sucked as dry as possible. The solid is transferred to a 600-cc. beaker, 250--300 cc. of methyl alcohol is added, and the mixture is warmed on the steam bath until the ester melts. It is then cooled in a freezing mixture while being stirred continuously the ester separates in a fairly fine state. It is then collected on a chilled funnel and allowed to dry in the air, preferably at a temperature, below 20°. The yield of ester is 152-156 g. (88-90 per cent of the theoretical amount based upon the dodecanol used). It melts at 20-250 (Note 2) and is sufficiently pure for most purposes. 

This is prepared by passing dry hydrogen chloride over chromium, or hydrogen over anhydrous chromium(III) chloride. It is a white solid. If pure chromium is dissolved in dilute hydrochloric acid in the absence of air, a blue solution of the hydrated chloride, containing the hexaaquo-ion [Cr(H20)6]2+. is obtained. The same solution is also obtained by reduction of the + 6 oxidation state (through the + 3) using a solution of a dichromate(VI) and reducing with zinc and hydrochloric acid ... 

Oeeurrence.— Always in combination—with sodium and other metals in sea Water, mid in the solid state in the salt.bcds of Cheshire, Worcester, Ac. Evolved from volcanoes in the form of hydrochloric acid. 

Raman spectra of N and N-labeled peroxynitrite in 0.3 M NaOH. The bottom spectra is for a sample of N-labeled peroxynitrite that has decomposed after adding a small amount of hydrochloric acid. The O NOO spectra revealed only five bands with a sixth band apparently obscured by the predominant nitrate peak. The sixth band can be resolved in solid state spectra (Tsai et ol., 1994). 

Hydrochloric add, on being boiled with lignin, turn red, and ultimately brown. In the solid state, it be-. comes black, but does not dissolve in the acid. When this substance is washed and dried, it burns with flame, bowing that it is only modified lignin, and not entirely carbonized. Fused potossa, or a strong solution of this alkali, changes a portion of the matter into oxalic and acetic acide, which combine with the base the alkaline liquor, when treated with acids, ports with a modified lignin which is blued by iodine. 

This reaction does not proceed in carbon tetrachloride solution.10 Retgers 11 stated that the solid hydride resulted when arsine was heated or when the flame of arsine impinged on a cold plate but other observers 12 maintain that arsenic alone is produced. A solid hydrogen-containing product has also been obtained by the action of zinc, in the presence of sulphuric and nitric acids, on arsenious oxide,13 and by the action of arsine on solid potassium hydroxide,14 followed by the addition of water. A good yield (up to 98 per cent.) of the hydride in a comparatively pure state may be obtained by mixing an ether solution of stannous chloride with a solution of arsenic trichloride in dilute hydrochloric acid.15 The reaction is ... 

Irradiation of 2,6-dimethylpyran-4-one (357) in ethanol or benzene or in the solid state yields the cage-like molecule (358) from which the pyran-4-one is regenerated by hydrochloric acid (63JA1208). When the photodimerization is conducted in water but in the absence of air, a small amount of 4,5-dimethylfuran-2-aldehyde is also formed (63JA2956). Pyran-4-one is photoisomerized to pyran-2-one (359) the intermediates postulated resemble those suggested in the irradiation of pyrylium salts (Section 2.23.2.1) (79JA7521). 

Electronic spectra of TcjClg in hydrochloric acid solution and in the solid state are qualitatively similar, indicating retention of the basic dimeric unit upon dissolution. The band maximum at 615 nm (e=185M 1 cm-1), originally reported as the major visible absorption (121), has not been reproduced in more recent publications, which locate this band at 638 nm (29, 70). Other solution maxima were present at 507 and 320 nm (29). 

A solute may be present as ions or as molecules. We can identify the form of the solute by noting whether the solution conducts an electric current. Because a current is a flow of electric charge, only solutions that contain ions conduct electricity. There is such a tiny concentration of ions in pure water (about 10-7 m) that water alone does not conduct electricity. A substance that dissolves to give a solution that conducts electricity is called an electrolyte. Electrolyte solutions (solutions of electrolytes), which conduct electricity because they contain ions, include aqueous solutions of ionic compounds, such as sodium chloride and potassium nitrate. The ions are not formed when an ionic solid dissolves they exist as separate ions in the solid but become free to move apart in the presence of water (Fig. 1.1). Acids also are electrolytes. Unlike salts, they are molecular compounds in the pure state but form ions when they dissolve. One example is hydrogen chloride, which exists as gaseous HC1 molecules. In solution, however, HCl is called hydrochloric acid and is present as hydrogen ions and chloride ions. 

Diazonium compounds are usually prepared in mineral acid solution, and the nitrous acid generated from sodium nitrite. Sufficient acid must be used to generate nitrous acid and to form the salt of the base, and still leave the solution acid. In practice 2J—2f mols. of hydrochloric acid are generally employed. In most cases it is essential that the reaction be carried out at about 0°, as many diazonium solutions decompose above this temperature. The reaction goes very readily in some cases but in others, and especially where an acid group is present, e.g., naphthylamine sul-phonic acids, the reaction is only carried out with difficulty. It is possible to diazotise a solid in suspension, but the reaction is usually very slow. If the solid is dissolved and reprecipitated in a fine state of division the action goes much more quickly. 

The sulfur, selenium, or tellurium in a moderately finely divided state is placed in a copper tube provided with an outlet and inlet. The outlet is connected to a train consisting of a trap cooled in a concentrated hydrochloric acid-ice mixture and then another immersed in liquid air or a solid carbon dioxide-alcohol mixture. Fluorine (synthesis 51) is passed into the inlet at the rate of 1 to 3 1. per hour. The reaction proceeds smoothly. The lower fluorides are condensed to a large extent in the hydrochloric acid-ice cooled trap, and the material collected in the liquid air or solid carbon dioxide trap consists principally of hexafluorides. 

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