Legal reagent

Legal reagent Solution I—0,5% of a recently prepared sodium nitroprussiate in water solution II—0.2 TV NaOH. Dissolve 2 mg of sample into pyndine (two to three drops), add one drop solution I, and four drops solution II (one at a time). A deep red color will be observed for cardiac glycosides and pink for a,p-unsatur-ated lactones and some p-,Y-lactones. (These should be kept under controlled pH since they may isomerize in alkaline solution.)... 

This spot-test reagent is now supplied water-wet since it has been found to be detonable and legally classifiable as an explosive. The editor has not heard of any problems in use. 

Label all vessels to indicate what they contain. An unlabeled bottle left and forgotten in a refrigerator or cabinet presents an expensive disposal problem, because the contents must be analyzed before they can be legally discarded. National Fire Protection Association labels shown in Figure 2-2 identify hazards associated with chemical reagents. A Material Safety Data Sheet provided with each chemical sold in the United States lists hazards and safety precautions for that chemical. It gives first aid procedures and instructions for handling spills. 

A useful starting point is to examine the characteristics of the pH control problem that make it difficult. The most fundamental reason for the difficulty is the stringency of the performance requirements, which may make it necessary to add reagent to within less than. 1 % of the ideal amount just to stay within legal limits on the pH of the treated stream. 

Remarks Reagents such as Legal (alkaline sodium nitroprusside solution), Baljet (alkaline picric add solution) or Raymond reagent (alkaline rn-dinitrobenzene solution) also give red., red-orange or violet (vis) cardenolide-specific colours. 

The Legal reachon forms the basis of the citrate identificahon test, and exactly the same methodology is used in the test 3.21. Lactates. In the first part of analysis the citric acid is oxidized to a substance that is susceptible to the nitroprusside reagent. 

Samples, reagents, solvents, and mobile phases on laboratory benches and shelves are labeled clearly and in accordance with (legal) requirements. Samples and specimens in refrigerators and freezers, are checked, for example, for expiration date, clear labeling. 

Do Not Place Any Liquid or Solid Waste in Sinks Use Appropriate Waste Containers. Many substances are toxic, flammable, and difficult to degrade it is neither legal nor advisable to dispose of organic solvents or other liquid or solid reagents by pouring them down the sink. 

Sulfites in foods or beverages need to be quantified to assure quality and compliance with legal regulations and to minimize the health risk to consumers. Because of its noticeable advantages, FIA has become one of the most widely used methods for determining sulfites. FIA gives a fast, simple and precise analytical response in real time, and small amounts of sulfite can be determined with low reagent consumption when small volumes of samples are available. The instrumentation is relatively simple and miniaturization is possible. It offers low interference and can be easily applied for routine analyses in control laboratories or industrial applications. 

It is quite impossible to ignore Legal s reaction when we deal with the use of Fe + and Fe " " in organic analysis. Legal s reaction is characteristic of a-methylene ketones or aldehydes. It involves nitroprusside ion as reagent. The reaction is carried out in alkaline medium, sodium hydroxide, ammoniac solution, ethylenedi-amine, piperidine, piperazine, sodium tetraborate, and sodium carbonate or hydrogen carbonate. 

Reagents 100 ml of cone, sulfuric acid are added carefully to 200 ml of water Schiff s and Legal s reagents (pp. 217 and 234). 

Procedure In a 100-ml flask 50 ml of H2SO4 are added to 1 g of the tested substance and the mixture is distilled. After several milliliters have been distilled aldehydes are detected with Schiff s reagent and ketones with Legal s reagent. 

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