Wijs reagent

Wigglers Wijs reagent Wij s solution Wild cherry Wild Musk Wiley melting point... 

The iodine value (IV) is used to determine the level of unsaturation in a fat/oil system. It is expressed as the number of grams of iodine that add to/react with 100 g of sample. The traditional iodine value method using the Wijs reagent requires carbon tetrachloride (CC14). For safety reasons, CC14 is no longer considered to be an acceptable chemical and it is not readily available for purchase, and if offered it is extremely expensive. Therefore the traditional method has been modified to a more human-friendly system which uses cyclohexane. 

Western blot, see Immunoblot Wet grinding, starch isolation, 674-676 Wheat and wheat starch enzymatic quantification, 682 isolation, 676 moisture content, 22 Whole-grain wheat, enzymatic quantification, 682 Wijs reagent, 467-468, 475 Wine, see also Grapes WUA. see Water uptake ability... 

The rate of reaction of ozone with amine was determined during the ozonization of rubber solution, where the reaction between ozone and rubber also proceeded concurrently. The extent of the reaction of rubber with ozone was calculated from the change in unsaturation of the rubber determined by the Wijs reagent. For example, SBR (Japan Synthetic Rubber, JSR 1502), purified by precipitation with acetone from benzene solution, was dissolved in carbon tetrachloride to give a 5% rubber solution. The rubber solution (20 ml.) was added with 80 ml. of carbon tetrachloride containing 1 X 10 3 mole of amine derivatives. Oxygen, containing 0.89% ozone, was introduced into the solution at 30°C. for 3 minutes at the rate of 550-560 ml./min. Under these conditions, all... 

Alternatively, where an estimated IV is available, the weight of sample (25 ml Wijs reagent used) may be obtained from Table 3. 

In this procedure, the polymer is reacted with an excess of standard iodine monochloride dissolved in glacial acetic acid ( Wijs reagent ) ... 

Dissolve 10 g sample in 50 mL CHCI3 and add 10 mL Wijs reagent (0.2 N, Riedel de Haen, no. 35071—this is a solution of iodine monochloride in glacial acetic acid). Let stand 30 min, then add 20 mL 15% KI solution and 100 mL water. Titrate with 0.1 N sodium thiosulfate solution to the starch end point, with vigorous stirring. Determine the reagent blank in the same manner. Calculation ... 

Iodine monochloride [7790-99-0] ICl, mol wt 162.38, 78.16% I, is a black crystalline soHd or a reddish brown Hquid. SoHd ICl exists ia two crystalline modifications the a-form, as stable mby-red needles, d = 3.86 g/mL and mp 27.3°C and as metastable brownish red platelets, d = 3.66 g/mL, mp 13.9°C and bp 100°C (dec). Iodine monochloride is used as a halogenation catalyst and as an analytical reagent (Wij s solution) to determine iodine values of fats and oils (see Fats and fatty oils). ICl is prepared by direct reaction of iodine and Hquid chlorine. Aqueous solutions ate obtained by treating a suspension of iodine ia moderately strong hydrochloric acid with chlorine gas or iodic acid (118,119). 

Iodine monochloride is used as an analytical reagent to determine iodine values of ods and fats. It is dissolved in glacial acetic acid (Wijs solution) for the analysis. ICl is used in organic synthesis. It also is used as a topical antiseptic. 

The method uses Wij s reagent, which is a 0.2mol/l solution of iodine monochloride in glacial acetic acid, and which is most conveniently purchased ready-made. The reaction with an unsaturated compound is addition across the double bond. This is traditionally represented as the addition of a molecule of iodine monochloride, but as it is necessary to... 

Using a burette or an automatic pipette, add 20.0 ml Wij s reagent (caution irritant and toxic vapour) and swirl to mix. 

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