Laboratory reagents

This is an important laboratory reagent and has the structure shown below ... 

Standards for food-grade chemicals in the United States are set by the Committee on Eood Chemicals Codex of the National Academy of Sciences (NAS) which pubHshes them in the Food Chemicals Codex (ECC) (6) (see also Eood additives). Standards for laboratory reagents are set by the American Chemical Society (ACS) Committee on Analytical Reagents and are pubHshed in Feagent Chemicals—A.CS Specifications (7). Standards for electronic-grade chemicals, which have extremely low limits for trace ions, are pubHshed aimually in The Book of SEMI Standards (BOSS) by Semiconductor Equipment and Materials International (SEMI) (8). 

Ammonium fluoride is a white, deflquescent, crystalline salt. It tends to lose ammonia gas to revert to the more stable ammonium bifluoride. Its solubiUty in water is 45.3 g/100 g of H2O at 25°C and its heat of formation is —466.9 kJ/mol ( — 116 kcal/mol). Ammonium fluoride is available principally as a laboratory reagent. If it is needed in large quantities, one mole of aqueous ammonia can be mixed with one mole of the more readily available ammonium bifluoride (1). 

The 30% reagent-grade hydrogen peroxide is purer than the industrial grades, is covered by ACS reagent specification, and is used as a laboratory reagent and in some specialty uses (see Fine chemicals). Several grades are also marketed for electronics use and thus have exceptionally low impurity levels. Some of these latter contain very Httie or no stabilizers (see Electronic materials). 

There is no fiiU-scale U.S. commercial production of thiophosgene, but it is available in glass ampuls from laboratory reagent suppHers. Thiophosgene may be produced in Israel as an intermediate for tolnaftate (2-naphthyl A/-methyl-A/-y -tolylthiocarbamate) [2398-96-17, an antifimgal dmg. 

The conversion of an alkene to an oxirane by an electrophilic oxidant (Scheme 72) is the commonest route to oxiranes (81H(15)517). The usual laboratory reagent is a peroxy acid... 

Ammonia is shipped as a liquefied gas under its own vapour pressure of 114 psig (7.9 bar) at 21°C. Uses are to be found in refrigeration, fertilizer production, metal industries, the petroleum, chemical and rubber industries, domestic cleaning agents and water purification. Aqueous solutions of ammonia are common alkaline laboratory reagents ca 0.88 solution is the strongest available. Ammonia gas is expelled on warming. 

The container glass is suitable for the storage of beverages, medicines, cosmetics, household products and a wide range of laboratory reagents. 

Alkanes are sometimes referred to as paraffins, a word derived from the Latin parum affinis, meaning "little affinity." This term aptly describes their behavior, for alkanes show little chemical affinity for other substances and are chemically inert to most laboratory reagents. They are also relatively inert biologically and are not often involved in the chemistry of living organisms. Alkanes do, however, react with oxygen, halogens, and a few- other substances under appropriate conditions. 

Eastman Organic Chemicals or B.D.H. Laboratory reagent grade diethyl oxalate was used. 

For practice in the method, the cyanide content of potassium cyanide (laboratory reagent grade) may be determined. 

Table J.l lists all the common strong acids in water. They include three common laboratory reagents—hydrochloric acid, nitric acid, and sulfuric acid (with respect to the loss of one proton from each H2S04 molecule). Most acids are weak in water. All carboxylic acids are weak in water.

L.28 Silver nitrate is an expensive laboratory reagent that is often used for quantitative analysis of chloride ion. A student preparing to conduct a particular analysis needs 100.0 ml. of 0.0750 M AgNO,(aq), but finds only about 60 mL of 0.0500 M AgNO,(aq). Instead of making up a fresh solution of the exact concentration desired (0.0750 M), the student decides to pipet... 

Hexanc is a very volatile aliphatic hydrocarbon. It is a constituent in the paraffin fraction of crude oil and natural gas and is also used as an industrial chemical and laboratory reagent. Laboratory grade -hexane contains approximately 99% w-hexane. "Hexane" or "hexanes" is a commercial and industrial product consisting of a mixture of hydrocarbons with six carbon atoms and includes -hexane and its isomers 2-methylpentane and 3-methylpentane as well as small amounts of other hydrocarbons (Brugnone et al. 1991). Laboratory and industrial solvents such as "hexane" and petroleum ether contain -hexane from <0.1% to as much as 33% (Creaser et al. 1983). Information regarding the chemical identity of -hexane is located in Table 3-1. 

Pasteur s salt solution analychem Laboratory reagent consisting of potassium phosphate and caicium phosphate, magnesium sulfate, and ammonium tartrate in distilled water. pa storz solt S3,lii-sh3n ... 

Pauling scale phys chem A numerical scale of electronegativities based on bond-energy calculations for different elements joined by covalent bonds. pol-iri Skal Pavy s solution analychem Laboratory reagent used to determine the concentration of sugars in solution by color titration contains copper sulfate, sodium potassium tartrate, sodium hydroxide, and ammonia in water solution. pa-vez S3,lu-sh3n Pb See lead. 

A recent summary of major domestic uses for chloroform noted the following percentage breakdowns typical of the early to mid-1990s (CMR 1995) use for manufacture of HCFC-22, 98% (refrigerants, 70% fluoropolymers, 30%) other miscellaneous uses, including laboratory reagents and extraction solvents for pharmaceuticals, 2%. 

Uses Solvent for celluloid, cellulose acetate, fats, oils, waxes, nitrocellulose and resins wood preservatives rayon and artificial leather imitation gold leaf extraction of resins and waxes in antifreeze mixtures and hydraulic fluids laboratory reagent preservative for animal tissue dyeing mixtures stripping agent for textiles. 

Uses Antiseptic and disinfectant pharmaceuticals dyes indicators slimicide phenolic resins epoxy resins (bisphenol-A) nylon-6 (caprolactum) 2,4-D solvent for refining lubricating oils preparation of adipic acid, salicylic acid, phenolphthalein, pentachlorophenol, acetophenetidin, picric acid, anisole, phenoxyacetic acid, phenyl benzoate, 2-phenolsulfonic acid, 4-phenolsulfonic acid, 2-nitrophenol, 4-nitrophenol, 2,4,6-tribromophenol, 4-bromophenol, 4-/ert-butylphenol, salicylaldehyde, and many other organic compounds germicidal paints laboratory reagent. 

Uses Manufacturing azo dyes, intermediates for antioxidants and accelerators for rubber photochemical measurements laboratory reagent dyeing hair and fur. 

Uses Laboratory reagent for detecting double bonds in organic compounds oxidizer in rocket propellants monopropellant increase octane rating for diesel fuel. 

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