Solubility dependence

The hydrocarbons are in general only slightly soluble in water. The solubility depends especially on the chemical nature of the hydrocarbons. 

These processes are based on the solubility of the H2S and/or GO2 within the solvent, instead of on chemical reactions between the acid gas and the solvent. Solubility depends first and foremost on partial pressure and. secondarily on temperature. Higher acid-gas partial pressures and lower temperatures increase the solubility of H2S and CO2 in the solvent and thus decrease the acid-gas components. 

MSH + MOH). Accordingly, solubilities depend sensitively not only on temperature but also on pH and partial pressure of H2S. Thus, by varying the acidity. As can be separated from Pb, Pb from Zn, Zn from Ni, and Mn from Mg. In pure water the solubility of Na2S is said to be 18.06g per 100 g H2O and for Ba2S it is 7.28 g. In the case of some less-basic elements (e.g. AI2S3, Cr2S3) hydrolysis is complete and action of H2S on solutions of the metal cation results in the precipitation of the hydroxide likewise these sulfides (and SiS2, etc.) react rapidly with water with evolution of H2S. 

However, solubility, depending as it does on the rather small difference between solvation energy and lattice energy (both large quantities which themselves increase as cation size decreases) and on entropy effects, cannot be simply related to cation radius. No consistent trends are apparent in aqueous, or for that matter nonaqueous, solutions but an empirical distinction can often be made between the lighter cerium lanthanides and the heavier yttrium lanthanides. Thus oxalates, double sulfates and double nitrates of the former are rather less soluble and basic nitrates more soluble than those of the latter. The differences are by no means sharp, but classical separation procedures depended on them. 

The usual means of identifying and quantifying the level of these additives in polymer samples is performed by dissolution of the polymer in a solvent, followed by precipitation of the material. The additives in turn remain in the Supernatant liquid. The different solubilites of the additives, high reactivity, low stability, low concentrations and possible co-precipitation with the polymer may pose problems and lead to inconclusive results. Another sample pretreatment method is the use of Soxhlet extraction and reconcentration before analysis, although this method is very time consuming, and is still limited by solubility dependence. Other approaches include the use of supercritical fluids to extract the additives from the polymer and Subsequent analysis of the extracts by microcolumn LC (2). 

Solubility depends on the nature of the IL and on solvation or complex formation. Most metal ions display preferential partitioning into water in IL aqueous systems and are hence less soluble in the IL than in water. 

In the ocean, inert gas concentrations tend to follow the temperature solubility dependence closely. This suggests that water parcels obtain their gas signatures when they are at the seasur-face close to equilibrium with the atmosphere at ambient temperature. 

It is widely recognized that the solvent in which any chemical reaction takes place is not merely a passive medium in which relevant molecules perform the solvent itself makes an essential contribution to the reaction. The character of the solvent will determine which chemical species are soluble enough to enter solution and hence to react, and which species are insoluble, and thus precipitate out of solution, thereby being prevented from undergoing further chemical change. In the case of water, as will be seen, polar and ionic species are the ones that most readily dissolve. But even so, mere polarity or ionic character is not sufficient to ensure solubility. Solubility depends on a number of subtle energetic factors, and the possible interactions between water and silver chloride, for example, do not fulfil the requirements despite the ionic nature of the silver salt. Hence silver chloride is almost completely insoluble in water. 

In general, solubility depends on the relative magnitudes of three pairs of interactions, namely solute-solute, solvent-solvent and solute-solvent (Robb, 1983). For a substance to be soluble in a given liquid, the solute-solvent interactions must be greater than or equal to the other two interactions. 

Lipids have been dehned on the basis of their stmctnre and solnbility. Lipids are natnrally occnrring componnds consisting of fatty acids and their derivatives, bile acids, pigments, vitamins, and steroids, as well as terpenoids, which are usually soluble in organic solvents such as benzene, chloroform, ether, and alcohol, etc., with variable solubility depending on the stmctnre of the lipid compound. 

Depending on the substituent, and to a lesser extent on the counterion, tetrazolium salts are generally crystalline colorless, or yellowish to orange solids. Although their solubility depends on the substituent pattern and the counterion, they are generally slightly soluble in water. Thus, tetrazolium... 

Cortes et al. [634] have recently used /rSEC-GC/LC in a comparative quantitative study of dissolution and dissolution/precipitation of PC/(2,4-di-f-butylphenol, nonylphenol isomers, Tinuvin 329, Irgafos 168) and ABS/(nonylphenol isomers, Tinuvin P, BBP, Vanox 2246, Tinuvin 328/770, Topanol CA, Acrawax). For the ABS sample the dissolution approach determined a four-fold higher concentration for Vanox 2246 than by dissolution/precipitation of the sample, indicating that precipitation can yield low (incorrect) results for additives which exhibit solubility dependence. Using both sample preparations equivalent concentrations were observed for the additives of the PC sample, except for Tinuvin 329. 

Solutions are mixtures, and therefore do not have definite compositions. For example, in a glass of water it is possible to dissolve 1 teaspoonful of sugar or 2 or 3 or more. However, for most solutions there is a limit to how much solute will dissolve in a given quantity of solvent at a given temperature. The maximum concentration of solute that will dissolve in contact with excess solute is called the solubility of the solute. Solubility depends on temperature. Most solids dissolve in liquids more at higher temperatures than at lower temperatures, while gases dissolve in cold liquids better than in hot liquids. 

McFarland et al. recently [1] published the results of studies carried out on 22 crystalline compounds. Their water solubilities were determined using pSOL [21], an automated instrument employing the pH-metric method described by Avdeef and coworkers [22]. This technique assures that it is the thermodynamic equilibrium solubility that is measured. While only ionizable compounds can be determined by this method, their solubilities are expressed as the molarity of the unionized molecular species, the intrinsic solubility, SQ. This avoids confusion about a compound s overall solubility dependence on pH. Thus, S0, is analogous to P, the octanol/water partition coefficient in both situations, the ionized species are implicitly factored out. In order to use pSOL, one must have knowledge of the various pKas involved therefore, in principle, one can compute the total solubility of a compound over an entire pH range. However, the intrinsic solubility will be our focus here. There was one zwitterionic compound in this dataset. To obtain best results, this compound was formulated as the zwitterion rather than the neutral form in the HYBOT [23] calculations. 

The following protocol represents a suggested method that will work well for many proteins. It is a blend of protocols used in the literature and recommended by Thermo Fisher in the Sulfo-SBED instruction manual. Modifications to reaction conditions may be necessary in certain cases to maintain protein stability or solubility, depending on the properties of the particular bait protein being used. 

The solubility of a solid in a relevant solvent medium is a crucial characteristic. Solubility is defined as the concentration of the dissolved solid (the solute) in the solvent medium, which becomes the saturated solution and which is in equilibrium with the solid at a defined temperature and pressure. The solubility depends on the physical form of the solid, the nature and composition of the solvent medium, the temperature, and the pressure [1],... 

In reverse, the surfactant precipitates from solution as a hydrated crystal at temperatures below 7k, rather than forming micelles. For this reason, below about 20 °C, the micelles precipitate from solution and (being less dense than water) accumulate on the surface of the washing bowl. We say the water and micelle phases are immiscible. The oils re-enter solution when the water is re-heated above the Krafft point, causing the oily scum to peptize. The way the micelle s solubility depends on temperature is depicted in Figure 10.14, which shows a graph of [sodium decyl sulphate] in water (as y ) against temperature (as V). 

APSQ Is soluble in a dilute aqueous solution of tetramethylam-monium hydroxide (TMAH). When APSQ was treated with trimethylsilyl chloride (TMSC1), the solubility of APSQ In the TMAH solution decreased, because silanol groups were terminated with TMS groups. This Indicates that APSQ Is alkali-soluble due to the presence of silanol groups. The solubility depended on the silanol content, which can be controlled by synthesis conditions or appropriate termination of silanol groups. APSQ obtained from Owens-Illinois PSQ was more soluble In TMAH solutions than that from Petrarch Systems, probably due to lower molecular weight (Mw). We used the former (Mw = 1,500) In this study. 

Figure 3. Calcium solubility dependence on bile salt preparation and concentration used in in vitro digestion (pH 6.8-6.9). Key ...

One of the first properties of hyperbranched polymers that was reported to differ from those of linear analogs was the high solubility induced by the branched backbone. Kim and Webster [31] reported that hyperbranched polyphenylenes had very good solubility in various solvents as compared to linear polyphenylenes, which have very poor solubility. The solubility depended to a large extent on the structure of the end groups, and thus highly polar end-groups such as carboxylates would make the polyphenylenes even water-soluble. 

You know intuitively that solubility depends on temperature. For most ionic compounds, more solute can dissolve in a solvent at higher temperatures. Chemists determine the solubility of an ionic compound by experiment, and then use the solubility data to determine Ksp. Like the equilibrium constant, Ksp is temperature-dependent. Therefore, different experiments must be carried out to determine Ksp at different temperatures. 

Three causes of extractant solubility in the aqueous phase may be distinguished solubility of un-ionized and ionized extractant and metal-extractant species. For extractants such as acids, amines, and chelating reagents, their polar character will always result in some solubility in the aqueous phase over the pH range in which they are useful for metal extraction. Solubility depends on many factors including temperature, pH, and salt concentration in the aqueous phase, as discussed in Chapter 2. 

Arsenic is historically the poison of choice for many murders, both in fiction and reality (e.g., Christie 1924 CNN 1998). The element is considered a metalloid (having both metallic and nonmetallic properties) and is widely distributed in the earth s crust. Arsenic occurs in trace quantities in all rock, soil, water, and air (WHO 2001). Under reducing conditions, arsenite (As ") is the dominant form, while arsenate (As ) generally is the stable form in oxygenated environments. Arsenic salts exhibit a wide range of solubilities, depending on pH and the ionic environment. 

Detailed discussions are available elsewhere (3,4) Solubility data obtained in this way for crystalline UO2 are shown in Figure 1 which also indicates how the solubility depends on acidity, redox-potential, and carbonate concentration (5),... 

Certain flavanone and chalcone glycosides are difficult to dissolve in methanol, ethanol, or alcohol-water mixtures. Flavanone solubility depends on the pH of water-containing solutions. 

The polymers are of high molecular weight they are film and fiber forming and their solubility depends on the nature of the substituent R. 

Pyroconversion Low to high solubility depending Used as coating materials for... 

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