Solubility relations

Curve A is clearly the solubility curve of C-S-H(I) scatter at the CaO-rich end may arise because a given Ca/Si ratio can be associated with more than one structural arrangement. However, any form of C-S-H that is structurally derived from 1.4-nm tobermorite or jennite, or perhaps more widely that is based on Ca-0 sheets, probably has a solubility lying on or close to this curve. There are no solubility data for C-S-H(II), 1.4-nm tobermorite or jennite, but one might expect the curves for the crystalline 

There are few data on the concentrations of CaO and SiO, in the pore solutions of C3S pastes (w/s 1.0), as opposed to suspensions, and those that exist are conflicting as regards Csjoz (B56,011). The values of after long times (e.g. 27mmol 1 ) (Oil) appear to be significantly above the solubility ofCH this has been attributed to incorporation of SiO, in the CH (W22), but might also be due to the small crystal size of some of this phase. 

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Selection of solvents. The choice of solvent will naturally depend in the first place upon the solubility relations of the substance. If this is already in solution, for example, as an extract, it is usually evaporated to dryness under reduced pressure and then dissolved in a suitable medium the solution must be dilute since crystallisation in the column must be avoided. The solvents generally employed possess boiling points between 40° and 85°. The most widely used medium is light petroleum (b.p. not above 80°) others are cycZohexane, carbon disulphide, benzene, chloroform, carbon tetrachloride, methylene chloride, ethyl acetate, ethyl alcohol, acetone, ether and acetic acid. 

Metathesis reactions are sometimes the reverse of those in aqueous systems because of the differing solubility relations. For example because AgBr forms the complex ion [Ag(NH3)2]" " in liquid NH3 it is readily soluble, whereas BaBr2 is not, and can be precipitated ... 

The complicated solubility relations, rates of hydrolysis, sclf-disproportionation and intcrcon-version with other phosphates depends sensitively on pH, eoncentration, temperature and ihc presence of impurities.Though of great interest academically and of paramount imporlaree industrially these aspects will not be further considered Triphosphates such as... 

Many of the most important naturally occurring minerals and ores of the metallic elements are sulfides (p. 648), and the recovery of metals from these ores is of major importance. Other metal sulfides, though they do not occur in nature, can be synthesized by a variety of preparative methods, and many have important physical or chemical properties which have led to their industrial production. Again, the solubility relations of metal sulfides in aqueous solution form the basis of the most widely used scheme of elementary qualitative analysis. These various more general considerations will be briefly discussed before the systematic structural chemistry of metal sulfides is summarized. 

Given its solubility, relate mass of solute to that of solvent. 

Titrations can be carried out in cases in which the solubility relations are such that potentiometric or visual indicator methods are unsatisfactory for example, when the reaction product is markedly soluble (precipitation titration) or appreciably hydrolysed (acid-base titration). This is because the readings near the equivalence point have no special significance in amperometric titrations. Readings are recorded in regions where there is excess of titrant, or of reagent, at which points the solubility or hydrolysis is suppressed by the Mass Action effect the point of intersection of these lines gives the equivalence point. 

For the purpose of investigating solubility relations at a given temperature in three-component systems of the type discussed above, the proportion of nonsolvent which must be added to produce incipient precipitation may be observed as a function of the polymer concentration. Isothermal phase diagrams like that shown in Fig. 123 may... 

Yalkowsky has shown that the solubility of a compound in a cosolvent mixture (S ) can be estimated through a log-linear solubility relation ... 

For interstitial solid solutions, too, the criteria used historically for the degree of solid solubility relates to elastic and electronic interactions. Experimentally observed maximum interstitial solubilities of H, B, C and N in Pd are inversely proportional to the sum of the s and p electrons, and hence are controlled by the valence electron concentration. Thus the electronic interactions dominate the... 

Apart from the qualitative observations made previously about suitable solvents for study, the subject of solvates has two important bearings on the topics of thermochemistry which form the main body of this review. The first is that measured solubilities relate to the appropriate hydrate in equilibrium with the saturated solution, rather than to the anhydrous halide. Obviously, therefore, any estimate of enthalpy of solution from temperature dependence of solubility will refer to the appropriate solvate. The second area of relevance is to halide-solvent bonding strengths. These may be gauged to some extent from differential thermal analysis (DTA), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) solvates of "aprotic solvents such as pyridine, tetrahydrofuran, and acetonitrile will give clearer pictures here than solvates of "protic solvents such as water or alcohols. 

Jones, H.P., Davey, R.J., Cox, B.G., 2005, Crystallization of a Salt of a Weak Organic Acid and Base Solubility Relations, Supersaturation Control and Polymorphic Behaviour, J. Phys. Chem. B, 109, 5273-5278. 

Volatile substances of which the vapours, on cooling, condense directly to crystals without passing through the liquid phase are sometimes advantageously purified by sublimation, particularly when solubility relations render recrystallisation difficult. The purification of iodine is a well-known case in point. In organic chemistry this process is particularly suitable for quinones. 

The titrations can be carried out both satisfactorily and effectively in such situations where the solubility relations offer erroneous and unsatisfactory results given by visual indicator and potentiometric methods. For instance ... 

Collander, R. The partition of organic compounds between higher alcohols and water, Acta Chem. Scand., 5 774-780,1951. Collett, A.R. and Johnston, J. Solubility relations of isomeric organic compounds. VI. Solubility of the nitroanilines in various liquids, J. Phys. Chem., 30(l) 70-82, 1926. 

Livingston, J., Morgan, R., and Richardson. A.H. Solubility relations in gas-liquid systems. IV. The solubility of oxygen in water as found by an anal3rtical method. J. Phys. Chem., 34(10) 2356-2366, 1930. 

The above set of equations can be solved numerically given input parameters, including initial bubble radius Uo, temperature, ambient pressure Pf, surface tension a, solubility relation, D and p as a function of total H2O content and temperature, and initial total H2O content in the melt. 

Dodson, C.R. and Standing, M.B. Pressure, Volume, Temperature and Solubility Relations for Natural Gas-Water Mixtures, Drill, and Prod. Prac., API (1944) 173-179. 

Fio. 2.—Solubility Relations" in the System Sucrose—Sodium Iodide—Water at 30°. 

Equilibrium properties also seem to show both types of anomalies illustrated in Figures 10A and 10E. As an example, we have discussed (31) the study by Klots and Benson (91) of the solubility ratio of nitrogen to argon. A solubility relation of the type shown in Figure 10A is observed in this case while other solubility data more frequently show the behavior indicated in Figure 10E. 

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