General solubility rules

The tendency to form boiler waterside deposits is partly dependent on factors such as the solubility of the particular mineral species and the strength of physical adherence involved. As a general rule, the rate of deposition tends to increase with higher levels of BW dissolved solids. Also, the rate of deposition increases with increase in heat-flux density and with the inadequate dosage, inappropriate feeding, or otherwise usage of antisealants and other deposit control agents (DCAs). 

The development of biphasic media requires a knowledge of general rules based on observation. The choice of the biocatalyst and the organic solvent is very important. Estimation of the biocatalyst tolerance to an organic solvent is based on various indicators, described later in this chapter. Biocatalysts are also sensitive to the process of the liquid-liquid interface. They can be used in two different forms free, soluble or immobilized. 

The solubility parameter of water is 17 or 23, depending on the association structure of water used in the calculation. None of the values listed in Table II are within two units of either value and by the general rules of the solubility concept, none of the polymers in Table II should be water soluble. Homopolymers of monomers c, e, or f in Figure 3 are not water soluble. The solubility values listed for the W-SPs studied do not correlate with the equilibrium pressures observed. A general correlation is noted if the values of the most hydrophobic segments (i.e., the oxypropyl, oxybutyl and acetate) are compared with PMVE. The... 

Some substances will dissolve in a particular solvent and others will not. There is a general rule in chemistry that states like dissolves like. Polar substances (such as alcohols) will dissolve in polar solvents like water. Nonpolar solutes (such as iodine) will dissolve in nonpolar solvents such as carbon tetrachloride. The mass of solute per 100 mL of solvent (g/100 mL) is a common alternative to expressing the solubility as molarity. It is necessary to specify the temperature because the solubility of a substance will vary with the temperature. The solubility of a solid dissolving in a liquid normally increases with increasing temperature. The reverse is true for a gas dissolving in a liquid. 

Properties and extraction processes Aquifer gas, also referred to as geo-pressured gas or brine gas, is natural gas found dissolved in aquifers, primarily in the form of methane. The solubility of natural gas, and thus the methane content of the water, can vary significantly, and depend on factors, such as the total pressure, temperature, salt content of the water and amount of other gases dissolved. The amount of gas dissolved in underground liquids increases substantially with depth. A general rule is that the deeper the aquifers and the higher the pressure, the higher the gas content. At depths down to 5 km, up to 5 m3 of methane can be dissolved per m3 of water in aquifers under normal hydrostatic pressure (load of water) under lithostatic pressure (load of water and rocks), this factor may increase to more than... 

Diffusion is generally measured as increase in mass, increasing and then levelling off at a saturation level which depends on the solubility coefficient. As a general rule the rate of mass increase and the time to equilibrium are proportional to the square of thickness. When the diffusion coefficient is known a suggested estimation of the time to reach equilibrium to a depth b is ... 

As mentioned before, certain covalent compounds, like alcohols, readily dissolve in water because they are polar. Since water is polar, and these covalent compounds are also polar, water will act as a solvent for them (general rule of solubility Like dissolves like ). Compounds like alcohols are nonelectrolytes—substances that do not conduct an electrical current when dissolved in water. However, certain covalent compounds, like acids, will ionize in water, that is, form ions ... 

The general rule of solubility is like dissolves like. This means that polar solvents dissolve polar solutes and nonpolar solvents dissolve nonpolar solutes. 

The solubility of polymers is determined by the interactions between macromolecules and the molecules of the solvent. But the prediction of the solubility of a macromolecule and hence the correlation to its chemical (and morphological) structure is much more complicated than for a low-molecular-weight compound. Nevertheless, some general rules do exist ... 

As a general rule, the addition of ethylene oxide to a resin backbone will tend to increase the water solubility of the compound. The addition of propylene oxide or butylene oxide to the resin will tend to increase the hydrocarbon solubility of the compound. Often, the dehazer or demulsifier can be made to perform selectively in oil-water systems by adding both ethylene oxide and propylene oxide to the same molecule. Performance and solubility of the alkoxylated compound can then be finely tuned by closely controlling the amount and order of epoxide addition. A random EO-PO based fuel demulsifier is shown in FIGURE 6-6. 

How can chemists measure the importance of solvents Solvents solubilize solutes. The general rule for organic or nonelectrolyte inorganic solutes, whether gaseous, liquid, or solid, is that they would show adequate solubilities. Expressions for the estimation of solubilities are presented in chapter 3. The effects on the rate of reactions will be discussed there, and comparisons made among classes of solvents. 

A summary of the discussion of solubility in this section is presented as properties of ions that favour solubility. The general rules are only guidelines, since there are exceptions and given with suitable examples. 

The solubility of potassium chlorate is depressed by the addition of other potassium salts, or by the addition of other chlorates F. Winteler, and T. Schlosing have measured the solubility of potassium chlorate in potassium chloride soln. and of sodium chlorate in soln. of sodium chloride. In accord with the general rule, the solubility is diminished by the addition of a salt with a common ion. S. Arrhenius measured the solubility of potassium chlorate in aq. soln. of potassium nitrate and C. Blarez in aq. soln. of potassium bromide, chloride, iodide, nitrate, sulphate, oxalate, and hydroxide H. T. Calvert, and J. N. Bronsted in an aq. soln. of the last-named compound. H. T. Calvert also measured the solubility of potassium... 

As a general rule, the solubility of copper ammine complexes in water and alcohols increases with the rise in coordinating power of the amine concerned the molecular weight of the latter is also involved. The following general... 

An increase in temperature generally causes an increase in the solubility of solutes. This general rule is followed by most proteins up to about 40°C. Above this temperature, however, many proteins aggregate and precipitate from solution. If the protein of interest is heat stable and still water soluble above 40°C, a major step in protein purification can be achieved because most other proteins precipitate at these temperatures and can be removed by centrifugation. 

Finally, some general rules for the amount of surfactant appear to be valid (13). For anionic surfactants the average size of droplets is reduced for an increase of surfactant concentration up to the critical micellization concentration, whereas for nonionic surfactants a reduction occurs also for concentrations in excess of this value. The latter case may reflect the solubility of the nonionic surfactant in both phases, causing a reduction of interfacial tension at higher concentrations, or may reflect the stabilizing action of the micelles per se. 

The liquid crystalline regions obey the general rules for the liquid phases, but only where the hydrocarbon content is high. Along the water-emulsifier axis the changes with temperature are small in the PIT range this indicates that the structure of the liquid crystalline phase depends mainly on short range emulsifier-water interactions, which limits the solubility of water into the emulsifier. 

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