RAST

III. Depression of the Freezing-point of Camphor (Rast s Method). 

The first synthesis of cinnoline was reported by von Richter in 1883. The diazonium chloride 5 which was obtained from o-aminophenylpropiolic acid (4), was heated in water at 70°C to provide the 4-hydroxycinnoline-3-carboxylic acid (6). When this acid 6 was heated above its melting point, carbon dioxide was liberated and 4-hydroxycinnoline (7) was obtained. Distillation of 4-hydroxycinnoline (7) with zinc dust furnished a small amount of oil, which was assumed to be cinnoline (8). The preparation of 4-hydroxycinnoline (7) was repeated by Busch and Klett, although in lower yield when compared to the original report. Busch and Rast later converted the 4-hydroxycinnoline (7) successfully to cinnoline (8) via the 4-chlorocinnoline (9). ... 

Rast, /. rest groove, notch catch, detent ... 

Raste, /. notch, indentation detent, rasten, v.i. rest halt. — v.t. Radio) tune. Raster, m. screen grating graph paper. 

Rast-gdrung, /. Brewing) arrested fermentation. -klinke, /. catch, detent, pawl, latch, rastlos, a. restless. 

The Rast method uses camphor (Ci0Hi O) as a solvent for determining the molar mass of a compound. When 2.50 g of cortisone acetate is dissolved in 50.00 g of camphor (kf = 40.0°C/m), the freezing point of the mixture is determined to be 173.44°C that of pure camphor is 178.40°C. What is the molar mass of cortisone acetate ... 

Learning about chemistry as a particular way of examining the natural world for example, being able to appreciate why warm salt water produces rast on iron objects ... 

One limitation of serum-specific IgE is that given the cross-reactivity between different Hymenoptera venoms, and also due to the presence of anti-carbohydrate antibodies, it is frequent to find several simultaneous positive results in patients with non-identified insect stings, a situation which makes diagnosis of the same difficult. In these cases, RAST inhibition and the release of histamine occasionally provide data on the venom involved and when this is not the case, it is advisable to administer immunotherapy against both [44]. 

Blanca M, Mayorga C, Torres MJ, Reche M, Moya MC, Rodriguez JL, Romano A, Juarez C Clinical evaluation of Pharmacia CAP System RAST FEIA amoxicilloyl and benzylpenicilloyl in patients with penicillin allergy. Allergy 2001 56 862-870. 

Reactions that involve the transfer of electrons are immensely beneficial in a vast range of chemical processes, from the operation of a battery to the transmission of nerve impulses. However, in the form of corrosion, electron-transfer reactions also can be highly destructive. The rasting of iron objects is a prominent example of corrosion. 

Corrosion of iron has serious economic impacts. Approximately 20% of the iron and steel produced in the United States is used to replace rasted metal, and the cost of replacing corroded materials is several billion dollars per year. Consequently, the prevention of corrosion is a major business. 

C20-0077. Several commercial rust removers contain the bidentate ligand oxalate, (O2 CC02) Explain how these household products remove rast. Include a structural drawing of the species that forms. 

Wittich RM, HG Rast, H-J Knackmuss (1988) Degradation of naphthalene-2,6- and naphthalene-1,6-disul-fonic acid by a Moraxella sp. Appl Environ Microbiol 54 1842-1847. 

Molshanova, I. V. (1968). Uptake of trace quantities of yttrium-91 and cerium-144 by plants from nutrient solutions and soil, Tr, Inst. Ekol. Rast. Zhivotn. Ural. Fil. Akad. Nauk SSSR 61, 31. 

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