Bleaching solution, preparation

A bleach solution was being prepared by mixing solid sodium chlorite, oxalic acid, and water, in that order. As soon as water was added, chlorine dioxide was evolved and later exploded. The lower explosive limit of the latter is 10%, and the mixture is photo- and heat-sensitive [1]. It was calculated that the heat of reaction (1.88 kJ/g of dry mixture) would heat the expected products to an adiabatic temperature approaching 1500°C with an 18-fold increase in pressure in a closed vessel [2],... 

A 100 mL flask was filled with Jacobsen s catalyst (26 mg), (Z)-methyl styrene (lmmol) and dichloromethane (1 mL). The solution was cooled with an ice-bath. To this solution was added the cold solution of bleach previously prepared (3.5 mL). 

A solution was prepared by mixing an aqueous solution of sodium hydro-genphosphate (0.05 M, 10 mL) and a solution prepared with concentrated bleach (sodium hypochlorite, 5mL) in water (20 mL). The pH of the resulting solution was adjusted to 11.25 by addition of few drops of hydrogen chloride 1 M or sodium hydroxide 1M. 

An overly efficient student simultaneously prepared two titration mixtures, consisting of diluted bleaching solution, KI solution, and HC1 solution. The student found that data from the two titrations yielded significantly different percents NaOCl in the commercial bleaching solution. Which determination would give the higher % NaOCl Briefly explain. 

A procedure for preparing concentrated sodium hypochlorite solution is given by Coleman and Johnson. Common bleach solution, such as Clorox, may also be used, although the volume of the solution is considerably increased. 

H is reasonably safe to handle if kept cold, but anything coming into contact with the liquid or its vapors should be washed thproughly with a bleach solution. H may be prepared in two ways - by adding hydrochloric acid to thiodiglycol or by bubbling ethylene gas through liquid sulfur dichloride (Levinstein process). The latter is the route we will take. While a simple process, the manufacture of H is extremely hazardous due both to the nature of the sulfur... 

Aqueous solutions of sodium hypochlorite (NaOCl), best known as household bleach, are prepared by reaction of sodium hydroxide with chlorine ... 

State was attained. After UV-light irradiation, about 80% of the absorbance at 580 nm was recovered. The conversion of 80% from 2a to 2b was almost the same as that in the solution phase. The conversion of the film prepared from 2a solution was 40%, which is half of the conversion of the film prepared from a solution of the closed-ring form isomer. This difference in the maximum conversion to 2b is caused by the conformation of the open-ring form isomers. The isomer has two conformations, anti-parallel and parallel conformations. The former is photoactive whereas the latter is inactive, and half of the open-ring form isomers are in the inactive parallel conformations in solution. Half of 2a molecules in the film prepared from 2a solution are in the inactive parallel conformation. The conformational change is difficult in the amorphous film below Tg. In contrast, 2a in the bleached film prepared from the solution of 2b is in an anti-parallel conformation, and the maximum conversion to 2b at the photostationary state is about two times larger than that in the film prepared from 2a solution. A similar increase in the conversions in the film prepared from the closed-form isomer has been observed in amorphous diarylethenes, 3-10. It should be noted that heat treatment of the bleached 7a film at a temperature above Tg resulted in a decrease in the maximum conversion, which indicates that conformational change takes place at temperatures above Tg. 

The reaction of chloro- or bromohydrins with bases provides an economical route for the preparation of epoxides. Halohydrins are readily accessible by treatment of an alkene with either hypochlorous acid (Clj -1- H2O —> HOCl), hypochlorite bleach solution (NaOCl), or hypobromous acid (NBS -1- HjO HOBr). These reactions involve the... 

Analyses of carefully crystallized Cl-TSP crystals from a liquor prepared from a phosphate liquor with a Na/P ratio between 2.7-3.0 and sufficient amounts of available chlorine from a bleach solution (Sunny Sol 150, Jones Chemicals, Inc., Calendonia, New York, 14423) show the composition of Cl-TSP crystals to be as follows ... 

Method of Preparing Bleached Solutions for Determination of Specific Rotations. 

Chlorine compounds are widely used as bleaching agents by the textile and paper industries. Some chlorine compoimds can bleach materials by oxidizing colored molecules. Chlorine compounds are also used as disinfectants. ITousehold bleach is a 5.25% solution of sodium hypochlorite (NaOCl) in water. Chlorine bleach is prepared commercially by passing an electric current through a solution of sodium chloride in water. As the sodium chloride breaks down, sodium hydroxide collects at the cathode and chlorine gas is generated at the anode. Sodium hydroxide and chlorine can then be combined to form sodium hypochlorite. 

The widespread application of fiberglass-reinforced plastic (FRP) composites has prompted comparative testing for resistance to bleaching solutions [107], Coupons were prepared in accordance with ASTM C 581 (Practice for Determining Chemical Resistance of Thermosetting Resins Used in Glass Fiber-Reinforced Structures Intended for Liquid... 

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