Trioxide Solution

The stopper is replaced by a thermometer, and the other side neck is equipped with a two-way adapter to hold a dropping funnel and a drying tube. The sulfur trioxide solution is cooled... 

Hazards With Xenon Trioxide Solutions ( Xenic Add ) , Talanta 14, Pergamon Press, N Ireland (1967), 871-3 [Accdg to this worker all Xe compds must be treated as potential sources of the expl Xe trioxide. Also, Xe fluorides and oxide fluorides, if contaminated with organic materials, should also be treated as sensitive expls]... 

The same method is given in BS 903 Part A3782 which also contains a national annex giving a second method for assessing the degree of corrosion when the rubber is not in contact with the metal. Zinc is used as the standard metal as this is fairly readily corroded. A strip of zinc and the rubber test piece are both suspended over distilled water in a stoppered container maintained at 50°C. After a period of three weeks, the corrosion products are removed from the zinc by immersion in chromium trioxide solution and the loss in weight used as the measure of degree of corrosion. This is a very sensitive method but even more care has to be taken than in the contact method to avoid contamination and to obtain reproducible results. 

Method 1. Cool a solution of 33 g (0.33 mol) of hydroquinone in 150 ml of 60 per cent acetic acid contained in a 600-ml beaker to below 5 °C in an ice bath. Dissolve 42 g (0.42 mol) of chromium trioxide in 70 ml of water, and add 30 ml of glacial acetic acid. By means of a separatory funnel with bent stem and supported over the beaker, add the chromium trioxide solution to the mechanically stirred hydroquinone solution at such a rate that the temperature does not rise above 10 °C the addition takes about 2 hours. Filter the mixture at once and wash the quinone several times with 10 ml portions of ice-cold water. Spread the material upon filter paper until dry, but no longer or the quinone will be lost through sublimation. The yield of quinone (a bright yellow crystalline solid), m.p. 115 °C, is 21 g (66%) it darkens when exposed to light. 

The mechanical stability and ion exchange capacity of these condensation resins were modest. A better approach is to prepare a suitable crosslinked base membrane, which can then be converted to a charged form in a subsequent reaction. Ionics is believed to use this type of membrane in many of their systems. In a typical preparation procedure, a 60 40 mixture of styrene and divinyl benzene is cast onto a fabric web, sandwiched between two plates and heated in an oven to form the membrane matrix. The membrane is then sulfonated with 98 % sulfuric acid or a concentrated sulfur trioxide solution. The degree of swelling in the final membrane is controlled by varying the divinyl benzene concentration in the initial mix to control crosslinking density. The degree of sulfonation can also be varied. The chemistry of the process is ... 

Cognate preparations. o-Nitrobenzaldehyde. Use 25 g (0.18 mol) of o-nitrotoluene and proceed as for p-nitrobenzaldehyde, but allow a period of 3 hours stirring at 5-10 °C after the addition of the chromium trioxide solution. In the work-up, omit the final ethanol washing to remove unchanged o-nitrotoluene boil the crude product under reflux for 30 minutes with 120 ml of light petroleum (b.p. 60-80 °C). The yield of o-nitrobenzylidene diacetate of m.p. 82-84°C is 16 g (36%). 

Procedure Unless otherwise directed, transfer about 100 mg of the sample, previously dried at 105° for 2 h and accurately weighed, into the boiling flask, and add 10 mL of chromium trioxide solution (60 g in 140 mL of water). Immerse the steam generator and the boiling flask in the oil bath (at room temperature) to the level of the top of the chromium trioxide... 

Make several reagent blank determinations, using only the chromium trioxide solution in the above procedure. The ratio of the sodium hydroxide titration (Vb) to the sodium thiosulfate titration (7b), corrected for variation in normalities, will give the acidity-to-oxidizing ratio, V b/Kb = K, for the chromium trioxide carried over in the distillation. The factor K should be constant for all determinations. 

Chemical Warfare symbol for Chlorsulfonic Acid-Sulfur Trioxide Solution (See). 

A xenon trioxide solution may be convenientlj analyzed by adding iodide and dilute perchloric or sulfuric acid, and then titrating the liberated triiodide with thiosulfate. The net reaction is ... 

Sulfur trioxide solution.. (23) Sulfur trioxide (SOi), about 55 per cent chlorsuUomc acid (HClSOi), about 45 per aeat by weight F8 None Screening agent While container is operating Same as summer Smoke irritation negligible... 

A 34-year-old woman with acute promyelocytic leukemia was given arsenic trioxide solution 0.1%, 10 ml/day for 7 days. A generalized skin rash appeared, and her serum transaminases rose. An electrocardiogram was normal. A second course of arsenic trioxide was used about 3 months later. She felt palpitation and mUd dyspnea and had complete atrioventricular block. Echocardiography showed a normal left ventricle. A thallium myocardial perfusion scan did not show a perfusion defect. Arsenic trioxide was withheld. Sinus rhythm returned 3 days later. Complete atrioventricular block recurred later when arsenic trioxide was re-administered, albeit in a lower dosage for a shorter period of time. 

Preparation. Rondestvedt and BordwelF cooled 800 g. of ethylene dichloride and distilled in sulfur trioxide from 60% fuming sulfuric acid or Sulfan B to a gain in weight of 300 g. The sulfur trioxide solution was cooled below —5°, and dioxane equivalent to the sulfur trioxide was added dropwise with stirring, when the complex separated as fine granules. This complex is much more reactive than sulfur trioxide-pyridine it is hydrolyzed by cold water. 

Corrigan it was not exploited synthetically until Corey prepared the reagent by addition of pyridine to neutral chromium trioxide solutions and used it for the oxidation of alcohols to aldehydes, ketones, and acids.xhe reagent is not acidic and the neutral conditions required for the oxidation are superior for the oxidation of allylic alcohols. In dichloromethane (nonaqueous workup) the oxidation is similar to that of PCC. Addition of catalytic amounts of pyridinium trifluoroacetate in dichloromethane significantly increases the rate of oxidation. Allylic alcohols are oxidized faster than aliphatic alcohols, making PDC the reagent of choice for this transformation. Cyclohexenol, for example, is oxidized 10 times faster than cyclohexanol with... 

For the determination of weight loss, the corrosion products have to be removed. Inhibited acids are normally used for this purpose, but it is important to be sure that such acids remove only the corrosion products and do not attack the base metal. For example, the following acids could be used inhibited hydrochloric acid for iron, sulfuric acid for copper, and chromium trioxide solutions for zinc. The chemical cleaning procedures for the removal of corrosion products are further described in ISO 8407 (3). The removal of corrosion products is also necessary to confirm homogenous corrosion and exclude possible local corrosion attack. 

Clean microscope slides Place slides into chromium trioxide solution in 80% (w/v) sulfuric acid (Merck, Rahway, NJ) for at least 3 h at room temperature. Wash slides in mnning water for 5 min, rinse them thoroughly in distilled water, and air-dry. Place slides in 100% ethanol, remove, and dry with a tissue immediately pnor to use (see Note 3). 

In the case of sulphur trioxide-alcohol systems the conductivity-composition curve reveals a maximum at 1 4-5 sulphur trioxide/alcohol molar ratio showing that the adducts formed are highly solvated. There is no break in the curve at a molar ratio 1 3, There are, however, breaks at 1 2 and 1 1 sulphur trioxide/alcohol molar ratios. The potentiometric, conductomeuic and visual titrations show that sulphur trioxide solutions in these alcohols behave as monobasic acids against nitrogen bases and indicate that the stable species in alcohol solutions are the tetracoordinated alkyl hydrogen sulphates which are monobasic ionizable acids. 

Write the formula for the molecular compound diboron trioxide. SOLUTION... 

E. Orban, The pll of Uranyl Sulfate-Uranium Trioxide Solutions, USAEC Report AECD-3580, Mound Laboratory, Aug. 14, 1952. 

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