Solubility limit

From an electrochemical viewpoint, stable pit growtli is maintained as long as tire local environment witliin tire pit keeps tire pit under active conditions. Thus, tire effective potential at tire pit base must be less anodic tlian tire passivation potential (U ) of tire metal in tire pit electrolyte. This may require tire presence of voltage-drop (IR-drop) elements. In tliis respect the most important factor appears to be tire fonnation of a salt film at tire pit base. (The salt film fonns because tire solubility limit of e.g. FeCl2 is exceeded in tire vicinity of tire dissolving surface in tlie highly Cl -concentrated electrolyte.)... 

Compounds which dissolve in concentrated sulphuric acid may be further subdivided into those which are soluble in syrupy phosphoric acid (A) and those which are insoluble in this solvent (B) in general, dissolution takes place without the production of appreciable heat or colour. Those in class A include alcohols, esters, aldehydes, methyl ketones and cyclic ketones provided that they contain less than nine carbon atoms. The solubility limit is somewhat lower than this for ethers thus re-propyl ether dissolves in 85 per cent, phosphoric acid but re-butyl ether and anisole do not. Ethyl benzoate and ethyl malonate are insoluble. 

The distinction between pairwise and bulk hydrophobic interactions is often made, although some authors doubt the existence of an intrinsic difference between the two ". Pairwise hydrophobic interactions denote the interactions behveen two isolated nonpolar solutes in aqueous solution. They occur in the regime where no aggregation takes place, hence below the critical aggregation concentration or solubility limit of the particular solute. If any breakdown of the hydrophobic hydration shell occurs, it will be only transient. 

In ulttafUttation, the flux,/ through the membrane is large and the diffusion coefficient, D, is small, so the ratio cjcan teach a value of 10—100 or mote. The concentration of retained solute at the membrane surface, may then exceed the solubility limit of the solute, and a precipitated semisohd gel forms on the surface of the membrane. This gel layer is an additional battier to flow through the membrane. 

The ions not only ate implanted in the surface, but cause considerable lattice damage displacing the host atoms. An amorphous layer maybe formed and the stmcture is not an equiUbtium one. Thus the solubility of the implanted ions may gteady exceed the solubility limit. AH of these effects combine to produce a hard case. 

Oxygen also dissolves in the silicon crystal lattice, forming SiO which may radically affect the electrical properties of the silicon. Oxygen is usually unintentionally introduced during the crystal-growing operation in concentrations up to the solubility limit (ca 2.5 x 10 atoms/cm ). When... 

Table 12. Solubility Limits and Electrical Conductivity Effects of Elemental Additions to Copper ...

The volume of ether solution must be reduced to approach the solubility limit of the triphenylene in ether before the chromatographic procedure. 

The chemical propjerties of the contaminants have to be considered when selecting separation techniques. Some of the liquids are absolutely immiscible in water, and if the process stream involves water and the contamination is liquid/liquid, then the separation technique can greatly reduce the volume of contaminated water. For example, if acetone is the contaminant of concern, a simple vap>or stripping technique can be effective in making a separation. In the case of refined oil, which has a solubility limit of approximately 50 ppm, one of the oil/water separation techniques could be effective. Some general guidelines to consider are ... 

The Freundlich liquid phase isotherm can be used to determine the effect of solubility on the adsorptive capacity of activated carbon over a range of different concentrations. Phenol is highly soluble due to its polar nature whilst, in comparison, tetrachloroethylene (PCE) has a low solubility due to being non-polar. In the isotherms illustrated, the concentration of phenol is low relative to its solubility limit and consequently, the adsorptive capacity peaks at 18% maximum (see Figure 9). In comparison the concentration of tetrachloroethylene is relatively close to its solubility limit and, accordingly, the adsorptive capacity is exceptionally good. 

The most commonly used remediation technique for the recovery of organic contaminants from ground water has been pump- and-treat, which recovers contaminants dissolved in the aqueous phase. In this regard, the application of carbon adsorption has found extensive, but not exclusive use. Vacuum extraction (also called soil venting) has also become popular for removal of volatile organic contaminants from the unsaturated zone in the gaseous phase. Both of these techniques can, in the initial remediation phase, rapidly recover contaminants at concentrations approximately equal to the solubility limit (pump-and-treat), or the maximum gas phase concentration of the contaminant (vacuum extraction). The... 

Pb2+ Tartrate buffer or chloride solution (solubility limits the amount of lead to less than 50 mg per 100 mL) 2 A 2-3 V... 

When sulfates, carbonates, and other dissolved BW salts exceed their individual maximum solubility limits, they form sludges, scales, and deposits. This situation may arise either from a general overconcentration of the BW TDS (high COC) or from the deliberate precipitation of salts of selective ions, as occurs when using phosphate precipitation programs. 

The poor solubility of higher sodium alkanesulfonates cited above is reflected in the surface tension vs. concentration plots of sodium pentadecane 4-sulfonate (Fig. 26). Because below the critical micelle concentration the solubility limit is reached, a break in the a-c plot occurs. The problem of solubility properties of alkanesulfonates below the point at which the hydrated crystals or solid... 

A 1 1 K-Zn phase is formed in amalgams when the content of neither of the metals exceeds its respective solubility limit in mercury. Heats of solution were determined. ... 

The increase in Ca is initiated rapidly and begins to recover after 1 min. The order of potency correlates fairly well with the solubilities of these compounds in organic solvents (37) and their abilities to accumulate in phospholipid vesicles (38), i.e., 6>y>a>p, but not with their insecticidal activity (y 6>a p 39). At these concentrations, crystals of p-, a-, and y-HCH were evident in the cell suspensions when we made simultaneous measurements of the right-angle light scatter, indicating that the order of aqueous solubilities is 6>y>a>p. However, stimulation by 6-HCH at concentrations below its aqueous solubility limit shows a typical dose dependency of the response (Figure 10). 

Daphnid Daphnia magna) MOTC 48-h EC50 (immobilization) >solubility limit (0.3 mg/l) >solubility limit (0.3 mg/l) Schering AG (1998f)... 

Solubility limits depend on the stabilization generated by solute-solvent interactions balanced against the destabilization that occurs when solvent-solvent interactions are dismpted by solute. Thus, we must examine intermolecular interactions involving water and alcohol molecules. 

The evaporation of water from a saturated solution leaves a solution in which the ion concentrations exceed the solubility limit. To return to equilibrium, the salt must precipitate from the solution. Evaporation is used to mine sodium chloride and other salts from the highly salty waters of inland seas such as Great Salt Lake in Utah and Israel s Dead Sea. 

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