Hydrochloric acid thiosulfate

Polyaniline (PANI) can be formed by electrochemical oxidation of aniline in aqueous acid, or by polymerization of aniline using an aqueous solution of ammonium thiosulfate and hydrochloric acid. This polymer is finding increasing use as a "transparent electrode" in semiconducting devices. To improve processibiHty, a large number of substituted polyanilines have been prepared. The sulfonated form of PANI is water soluble, and can be prepared by treatment of PANI with fuming sulfuric acid (31). A variety of other soluble substituted AJ-alkylsulfonic acid self-doped derivatives have been synthesized that possess moderate conductivity and allow facile preparation of spincoated thin films (32). 

A double end point, acid—base titration can be used to determine both sodium hydrosulfide and sodium sulfide content. Standardized hydrochloric acid is the titrant thymolphthalein and bromophenol blue are the indicators. Other bases having ionization constants in the ranges of the indicators used interfere with the analysis. Sodium thiosulfate and sodium thiocarbonate interfere quantitatively with the accuracy of the results. Detailed procedures to analyze sodium sulfide, sodium hydro sulfide, and sodium tetrasulfide are available (1). 

The existence of anhydrothiosulfuric acid [83682-21-7] has been proposed to explain the apparent stabiUty of thiosulfate in concentrated hydrochloric acid solution (16) ... 

Analytical and Test Methods. An aqueous solution of sodium thiosulfate forms a white precipitate with hydrochloric acid and evolves sulfur dioxide gas which is detected by its characteristic odor. The white precipitate turns yellow, iadicatiug the presence of sulfur. The addition of ferric chloride to sodium thiosulfate solutions produces a dark violet color which quickly disappears. 

A mixture of 17 g of the methiodide and 32 ml of a 40 % aqueous potassium hydroxide solution is heated with stirring in a flask fitted with a condenser. The heating bath should be kept at 125-130°, and the heating should be continued for 5 hours. The cooled reaction mixture is then diluted with 30 ml of water and washed twice with 25-ml portions of ether. The aqueous layer is cautiously acidified in the cold with concentrated hydrochloric acid to a pH of about 2 and then extracted five times with 25-ml portions of ether. The combined extracts are washed twice with 10% sodium thiosulfate solution and are dried (magnesium sulfate). Removal of the solvent followed by distillation affords about 3 g of 4-cyclooctene-l-carboxylic acid, bp 125-12671-1 mm. The product may solidify and may be recrystallized by dissolution in a minimum amount of pentane followed by cooling in a Dry-Ice bath. After rapid filtration, the collected solid has mp 34-35°. 

The benzoylperoxide used was analyzed by dissolving r g. in 25 cc. of dry ether and adding 2 cc. of 5 per cent sodium ethylate solution, keeping the temperature below — 50. The ether solution was extracted with exactly 100 cc. of cold water and an aliquot part of the aqueous extract taken. To this was added 2 cc. of 5 per cent potassium iodide and 2 cc. of dilute hydrochloric acid and the liberated iodine was titrated with 0.1 N sodium thiosulfate solution. The peroxide analyzed 90 per cent pure. 

Certain older reports [14] on the existence of extremely sulfur-rich sulfanes in mixtures of high sulfur content obtained from sodium thiosulfate and hydrochloric acid are in error since elemental sulfur was shown to be the main component besides traces of H2S [15]. 

Mond A process for recovering sulfur from the residues from the Leblanc process. The sulfur is partially oxidized to thiosulfate and converted to elemental sulfur by adding hydrochloric acid. This process recovers only half the sulfur it was supplanted by the Chance process. Invented by L. Mond and operated by the Netham Chemical Company at Bristol from 1868 to 1888. 

Isonicotinic Acid Methochloride. To a slurry of 246 g of isonicotinic acid in 3.2 liters of methanol and 300 ml of water containing 88 g of sodium hydroxide has 355 g of methyl iodide added to it. Note Isonicotinic acid can be replaced with nicotinic acid, thus producing B-pethidine, instead of demerol. There is very little difference in potency between these two dmgs and the formula does not change Oust use an equimolar amount of nicotinic acid), so you may use either acid. Stir and reflux the above mixture for 60 hours, then remove the methanol with vacuo. Use sodium thiosulfate to reduce iodine to iodide and add water to give a volume of 1.5 liters. Use hydrochloric acid (coned) to get a ph of 2.0. 

A mixture of a solution of 0.300 g of an alkyl methanesulfonate or p-toluenesulfonate in 3-6 ml of 1,2-dimethoxyethane, 0.300 g of sodium iodide, 0.300 g of zinc dust, and 0.3 ml of water is stirred and refluxed for 4-5 hours. After dilution with ether the mixture is filtered the solution is washed with water, with 5% aqueous hydrochloric acid, with 5% aqueous solution of potassium hydrogen carbonate, with 5% aqueous solution of sodium thiosulfate and with water. After drying with anhydrous sodium sulfate the solution is evaporated and the residue worked up, giving 26-84% yield of alkane. 

Addition of hydrochloric acid to aqueous sodium thiosulfate results in the precipitation of elemental sulfur according to the above equation (Sect. 2). Solvent extraction (CHCI3 or toluene) of this sulfur yields yellow solutions from which Sg crystallizes... 

Sodium thiosulfate reacts with chlorine to form sodium bisulfate and hydrochloric acid. This reaction removes chlorine from aqueous solutions ... 

Sodium thiosulfate reacts with hydrochloric acid, decomposing to sulfur and sulfur dioxide ... 

A sample (approximately 0.2 g.) is weighed accurately and dissolved in 25 ml. of water then 25 ml. of 0.1 N hydrochloric acid and 0.2 g. of potassium bromide are added. The solution is titrated with 0.017 M potassium bromate until a permanent yellow color is produced. Potassium iodide (0.1 g.) is added, and the solution is backtitrated to a starch end point with 0.1 N sodium thiosulfate. The blue color returns in about a minute since the high acidity promotes air oxidation of excess iodide. The accuracy is only slightly less if the appearance of a faint yellow bromine color is taken as the end point. One mole of potassium bromate is equivalent to 3 of sodium /8-styrenesul-fonate. 

To a stirred solution of 120 ml of methylene chloride, 18 ml of dry pyridine, and 5 ml of iodine pentafluoride maintained at —10°C to —20°C in a Dry Ice-carbon tetrachloride slurry is added a solution of 13.5 gm (0.1 mole) of cumyl-amine in 10 ml of methylene chloride over a 1 hr period. The reaction mixture is stirred for another hour at —10°C, and then for 1 hr at 0°. After this time, water is added to the reaction mixture and stirring is continued until the yellow solid which had formed is dissolved. The lower organic layer is separated and washed in turn with water, 1 N hydrochloric acid, a saturated sodium thiosulfate solution, and again with water. After drying with anhydrous magnesium sulfate and filtration, the product solution is partially evaporated by means of a rotary evaporator at a temperature below 30°C. The brown solid obtained on cooling is separated and recrystallized twice from methylene chloride yield 4.75 gm (17.9%), m.p. 86.9°-88.7°C. 

To a stirred methylene chloride solution of 4.62 gm (15 mmoles) of 1-phenyl-2-(diphenylphosphine oxide)hydrazine maintained at —20°C is added over a 10 min period 2.67 gm (15 mmoles) of iV-bromosuccinimide. The solution is allowed to warm to room temperature, and stirring is continued for 10 min. The solids formed are removed by filtration and discarded. The solution is washed in turn with two portions of 5 % aqueous sodium thiosulfate solution, 0.1 N hydrochloric acid, water, dilute aqueous potassium bicarbonate, and again water. The methylene chloride solution is dried over anhydrous sodium sulfate and filtered. The filtrate is evaporated to incipient crystallization at room temperature at reduced pressure yield 4.1 gm (90%), m.p. 105°-106°C. 

The colloid is prepared by rapidly mixing dilute solutions of sodium thiosulfate and hydrochloric acid so that the final concentration of each is about 0.002 M. The following reaction then occurs so slowly that the sulfur precipitates only on those particles that nucleate first ... 

DISSOLVE A FEW CRYSTALS OF HYPO (SODIUM THIOSULFATE] IN % TEST TUBE WATER. ADD 1 DROP OF HYDROCHLORIC ACID. SOON LIQUID TURNS MILKY OF EXCEEDINGLY FINE PARTICLES OF SULFUR. 

DISSOLVE Vi TEASPOON HYPO (SODIUM THIOSULFATE) IN 40 ml WATER. ADD A FEW ml HYDROCHLORIC ACID. SULFUR DIOXIDE AND PRECIPITATE OF SULFUR RESULT. 

The concentration of the hypochlorous acid solution is determined by adding a measured volume to an excess of potassium iodide solution acidified with hydrochloric acid, and titrating with standard thiosulfate solution. Usually the concentration is found to be between 3.5 and 4 per cent. The amount necessary to react with 123 g. (1.5 moles) of cyclohexene is calculated. 

A yellow precipitate is produced in the reaction between sodium thiosulfate and hydrochloric acid. 

The rate of this reaction can be followed by recording the time taken for a given amount of sulfur to be precipitated. This can be done by placing a conical flask containing the reaction mixture on to a cross on a piece of paper (Figure 7.8). As the precipitate of sulfur forms, the cross is obscured and finally disappears from view. The time taken for this to occur is a measure of the rate of this reaction. To obtain sufficient information about the effect of changing the concentration of the reactants, several experiments of this type must be carried out, using different concentrations of sodium thiosulfate or hydrochloric acid. 

The reaction between sodium thiosulfate and hydrochloric acid can also be used to study the effect of temperature on the rate of a reaction. Figure 7.11 shows some sample results of experiments with sodium thiosulfate and hydrochloric acid (at fixed concentrations) carried out at different temperatures. You can see from the graph that the rate of the reaction is fastest at high temperatures. 

Make a colloidal sol of iron(m) hydroxide by adding aqueous iron(m) chloride to boiling water, or a colloidal sulfur sol by adding dilute aqueous sodium thiosulfate to hydrochloric acid. For both of these sols, it can be shown that the solid phase is not separated by filtration. 

Identical mixtures of sodium thiosulfate solution and hydrochloric acid are used at different temperatures in the experiment described on... 

If the trichloride is pure, the volume of the thiosulfate will be six times the volume of the 0.1N hydrochloric acid. Any excess of thiosulfate will indicate that the trichloride contained some free chlorine and will be a measure of the amount. 

Small Quantities. Wear nitrile rubber gloves, eye protection, and laboratory coat. In the fume hood, cautiously add iodine (5 g) to a solution of sodium thiosulfate (300 mL of 4%) containing sodium carbonate (0.1 g). Stir until all of the iodine has dissolved (solution is colorless), and then neutralize with sodium carbonate. When reduction is complete, add sodium carbonate or dilute hydrochloric acid to neutralize the solution. Wash into the drain.19... 

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