Decomposition solution

Diazonium compounds are usually very soluble in water, and cannot be readily isolated, since on warming their aqueous solutions, decomposition occurs with the formation of a phenol ... 

Sodium borohydride and potassium borohydride [13762-51 -1] are unique among the complex hydrides because they are stable in alkaline solution. Decomposition by hydrolysis is slow in water, but is accelerated by increasing acidity or temperature. 

The first-order decomposition rates of alkyl peroxycarbamates are strongly influenced by stmcture, eg, electron-donating substituents on nitrogen increase the rate of decomposition, and some substituents increase sensitivity to induced decomposition (20). Alkyl peroxycarbamates have been used to initiate vinyl monomer polymerizations and to cure mbbers (244). They Hberate iodine quantitatively from hydriodic acid solutions. Decomposition products include carbon dioxide, hydrazo and azo compounds, amines, imines, and O-alkyUiydroxylarnines. Many peroxycarbamates are stable at ca 20°C but decompose rapidly and sometimes violently above 80°C (20,44). 

A similar distribution of copper reagents can be obtained via the du ect reaction of copper metal with dibromodifluoromethane or bromochlorodifluoromethane in DMF at 85-95 °C [2J2] The oligomerization can be supressed via the addition of alkali metal fluorides to the reaction mixture [272] When HMPAis added to the trifluoromethylcopper solution, decomposition is slowed, and this solution can be used to trifluoromethylate aromatic iodides [270] (equation 143). 

High-temperature baths reduce surface tension and viscosity, thus decreasing drag-out volume. Disadvantages to be considered are more rapid solution decomposition, higher energy consumption, and possible dry-on pattern on the workpiece. 

Tc(III), Tc(IV) and Tc(V) P-diketonate complexes are stable in acid solution. In fact, when a chloroform solution of TcCl2(acac)2 was shaken with 1 M hydrochloric acid solution, no detectable change in the distribution ratio of the complex - defined as the ratio of the concentration of technetium in the organic phase to that in the aqueous phase - was observed over a 24 h period [26]. However, when the technetium complexes were backextracted into aqueous alkaline solution, decomposition occurred [26-29]. In all the cases studied, spectrophotometric investigation revealed that pertechnetate was formed quantitatively as a final product. 

A yellow solution is formed when nitrous acid is added to thiosulphate ion in water84. This is believed to be due to the formation of nitrosyl thiosulphate [O3SSNOI, although this has not been isolated and even in solution decomposition is fairly rapid. The equilibrium constant for its formation Wxno is 1.66 x 107 dm6 mol 2 at 25 °C and the UV-visible absorption spectrum is very similar to that of other S -nitroso compounds85. The rate constant for its formation is very large and is believed to represent a diffusion controlled process. Thiosulphate ion does appear to catalyse nitrosation but, over the range studied... 

It is interesting to note that only one peak resulted from DPH injection. Occasionally, it was found that a second, later eluting peak was present..., but this was not always the case. This additional component may have been a solution decomposition product."... 

The easiest way to 10 goes via the synthesis of KDNM (see Section n.C). Acidification of an aqueous solution of KDNM, which should be buffered with H3PO4 (pH = 6.5), followed by low-temperature extraction with diethyl ether, gives the monomeric emerald-green nitrosolic acid 10 dissolved in the ether phase. Slow removal of the solvent yields the yellowish dimeric form of 10. The acid (10) is only poorly characterized. It is known to slowly decompose into HCN and HNO2 in basic solution (decomposition of the anion DNM), while the free acid (10) rapidly decomposes to give fuhninic acid, HCNO and hyponitrous acid, HON=NOH. It should be noted that both the free acid and its metal DNM salts are highly explosive. 

It is now clear that the plate theory has a wide field of application. Its use, however is not restricted to LC. For example, the plate theory can be used to Investigate temperature changes that take place in a GC column,(3), pressure changes that take place in a GC column, (4), the effect of solute decomposition on band profile and other similar effects that can take place in a chromatographic system. The plate theory has many areas of application that still remain to be explored. 

New examples of the formation of pyrazolo[3,4-r/ [l,2,3]triazoles from 4-aminopyrazoloureas, described above in Section 10.05.9.1.2(vii)), have been described. The recent publication of Maggio and co-workers provides an insight into the mechanism of the reaction. It has been shown that nitrosation of 230 with nitrous acid at 0°C followed by adjustment of the pH to 8 and room temperature extraction furnishes, from amongst a mixture of products, the 5,5-bicycle 231 whilst extraction and work-up at 0°C yielded the 5,7-bicycle 232 as the single reaction product. The latter is the precursor to the pyrazolotriazole which results simply from room temperature solution decomposition involving loss of (m)ethyl isocyanate. The formation of the triazole 231 from the tetrazepinone 232 is rationalized as shown in Scheme 48 <2006ARK120>. 

When silver sulphite or a mixture of sodium sulphite and silver nitrate is heated in boiling aqueous solution, decomposition occurs with formation of silver dithionate.1... 

This is clearly illustrated in the case of p-GaP as shown in Figure 5. In a 0.1 M NaOH solution decomposition is by Ga loss from the surface as the hydroxide, and photocurrent decay is rapid as a phosphate layer builds on the surface. In 0.1 M HgPO solution decay is again rapid but in this case the Ga is not solubilized but deposits on the surface as the metal. In the more oxidizing acids such as H2SO4 both Ga and P are removed from the surface and the photocurrent remains high as the surface is essentially photoetched. 

Rate of complex formation between chiral alcohols and DBTA monohydrate in hexane suspension is quite slow (see Figure 1) and numerous separation steps are necessarry for isolation of the alcohol isomers (filtration of the diastereoisomeric complex then concentration of the solution, decomposition of the complex, separation of the resolving agent and the enantiomer, distillation of the product). To avoid these problems, alternative methods have been developed for complex forming resolution of secondary alcohols. In a very first example of solid phase one pot resolution [40] the number of separation steps was decreased radically. Another novel method [41] let us to increase the rate of complex forming reaction in melt. Finally, first examples of the application of supercritical fluids for enantiomer separation from a mixture of diastereoisomeric complexes and free enantiomers [42, 43] are discussed in this subchapter. 

Figure 4.4 Reprinted from Tribol. Int., Vol. 31, M.L.S. Fuller, M. Kasrai, G.M. Bancroft, K. Fyfe and K.H. Tan, Solution decomposition of zinc dialkyl dithiophosphate and its effect on antiwear and thermal film formation studied by X-ray absorption spectroscopy, pp. 627-644. Copyright 1998, with permission from Elsevier.

Toluene and xylenes were removed with similar efficiency at low concentration. At high concentration, toluene was removed at a rate twice that of the xylenes, perhaps due to increased participation by the H atom. For high concentrations of toluene and xylenes, OH scavenging may have been compensated for by H atom attack. This may then have become the dominant mechanism of solute decomposition. Information such as this may be important in predicting by-product distributions when treating water of varying quality. 

Table 7 The Effect of Ozone Addition on Solute Decomposition in Irradiated Water... 

The complex is reasonably stable in acidic solution, decomposition (i.e., aquation) ... 

The yellow hexaammineruthenium(II) cation is a moderately strong reducing agent and will, for example, reduce hydrogen chloride, mercuric chloride, gold(III) chloride,1 and the hexa-amminecobalt(III) cation.6 The dry complexes are stable for a matter of weeks, especially when kept cold, but in aqueous solution decomposition is more rapid. 

Ammonia solution decomposition occurs with the separation of gelatinous silicic acid. 

In acid solution decomposition is extremely rapid and H2S204 is unknown under any conditions. The Zn and Na salts are commonly used as powerful and rapid reducing agents in alkaline solution ... 

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