Variation with concentration

Fig. 3. Schematic diagram for the variation with concentration of the partial molar heat of solution of the liquid noble metals into liquid tin, taken from reference 51. The numbers are the experimental and calculated AHt for the solutes, in cal/g atom, at the two concentrations of 0 and 0.02 mole fraction. Q-C labels the curves calculated by the quasichemical theory in first order B-W labels the curves calculated by the Bragg-Williams, or zeroth-order approximation, which assumes a random...

Fig. 17. Variation of conductivity of Ag-starch nanocomposites with temperature. Inset shows variation with concentration of silver nanoparticles.

Hall, P., and Selinger, B., A Statistical Justification Relating Interlaboratory Coefficients of Variation with Concentration Levels, Anal. Chem., 61, 1989, 1465-1466. 

For polystyrene fractions in diethyl phthalate solution (30000average value of 1.6 x 10 18 ( 50%). In dilute solution e/36M is 1.27 x 10 18 for polystyrene (21). No systematic variations with concentration, molecular weight or temperature were apparent, the scatter of the data being mainly attributable to the experimental difficulties of the diffusion measurements. The value of Drj/cRT for an undiluted tagged fraction of polyfn-butyl acrylate) m pure polymer was found to be 2.8 x 10 18. The value of dilute solution data for other acrylate polymers (34). Thus, transport behavior, like the scattering experiments, supports random coil configuration in concentrated systems, with perhaps some small expansion beyond 6-dimensions. 

With lactose, variation with concentration is negligible [a] ° — + 52-53° for the hydrated sugar, + H20.2 This number diminishes... 

With raffinose, the variation with concentration or temperature is very slight, the value for the hydrate (+ 5H20)3 being + 104-5°. This value is 1-5715 times that for saccharose, while the value for anhydrous raffinose is 1-1786 times that for hydrated raffinose and 1-852 times that for saccharose. 

The mixtures of the second section in Table 6, which were investigated earlier (when erroneous conclusions were drawn)77, all show double dispersion. The details for one mixture, SF6+C2F4, are shown in Fig. 16. There is near-resonance between the lowest (344 cm-1) mode of SF6 and the first harmonic of the lowest (190 cm-1) mode of C2F4. C2F4 shows very efficient homomolecular vibration-translation transfer, and the estimated vibration-vibration transfer rate (ZAB=70) falls between this and the slower vibration-translation transfer rate of SF6 (ZAA = 1005). Double dispersion is observed, and the predicted linear variation with concentration of the two relaxation times. The remaining mixtures in this section, all of which involve B components whose homomolecular relaxation is very rapid, behave similarly. 

Up till about 1921, it was often supposed that the potential could be identified with the single potential difference at the phase boundary. Freundlich and his collaborators1 showed that this is quite impossible, since the variation with concentration, and the influence of adsorbed substances, are entirely different in the two cases sometimes indeed the two potentials may have different signs. The phase boundary potential, if defined as the Volta potential, is the difference between the energy levels of the charged component, to which the phase boundary is permeable, inside the two phases when these are both at the same electrostatic potential. We have seen that it is difficult, or impossible, to define the phase boundary potential in any other way (see 2 and 3). It includes the work of extraction of the charged component from each phase, and this includes the part of the double layer which according to Stern s theory is fixed. The potential is merely the potential fall in the mobile, diffuse part of the double layer, and is wholly within one phase. 

Fig. 11. Assumed variations with concentration of the parameters used in computing the curves of Fig. 10 a (C,<—o /( , — o...

Figure 8 shows an example of HaOe measurements made under relatively polluted conditions and Figure 9 shows measurements made under relatively clean conditions. Both studies showed similar diurnal variations with concentrations reaching maxima in the afternoon and minima during the night. The mixing ratios reach higher values in the clean air conditions. 

Calculate the distribution constant k from the results of runs 1 to 3. Plot versus the iodine concentration in the CCI4 solution, (l2)cci,- If k is not constant, discuss its variation with concentration. 

For an ideal solution, then, a plot of n,ic versus c should be a straight line at constant temperature. But, as you might expect, there is a variation with concentration (Figure 12-7). Just as with real gases, however, the data can be fit to the polynomial we call a virial equation. But, what do we do about polymers that have a distribution of molecular weights ... 

Figure 9 Comparison of measured variation with concentration of permittivity of electrolytic solutions " with calculations from Clueckauf s continuous model, which gives the full line...

I In some ways the nomenclature is a little confusing. In nmr it is traditional to use Ti and to describe the relaxation times of specific nuclear processes and t the mean lifetime of a nucleus in a particular state. In chemical relaxation methods, however, t refers to the relaxation time. Chemical relaxation methods and nmr are similar in that in each, one time function is measured and its variation with concentration is followed. The difference comes in the relationships of the respective time functions to the concentrations. 

It is clear from these figures that the Fick D shows a significantly greater variation with concentration than does the Maxwell-Stefan ). A particularly extreme example of the strong composition dependence of D is afforded by the system methanol-n-hexane in the vicinity of the spinodal curve. The experimental data for this system (obtained by Clark and Rowley, 1986) are plotted in Figure 4.1(6/) the values of D vary by a factor of almost 20 The Maxwell-Stefan ), calculated from Eq. 4.1.5 varies by a factor of only 1.5. 

Elucidating the details of sugar and water interactions amounts to differentiating between the behaviour of a thin layer in contact with the solute from that of the bulk of water molecules surrounding it. We can observe variations with concentration of certain solvent properties concerning their oxygen or hydrogen atoms, or of the entire molecule, and they are interpreted as an effect of perturbations... 

One point that was not focused on in the discussion of the partition coefficients of pentanol in SDS given above, is the possible variation with concentration. It is conceivable that the distribution coefficients vary with both solute and surfactant concentration. If we look first at the variation with surfactant concentration, values based on thermodynamic data are the most abundant. The calculation of partition coefficients from thermodynamic data do in most cases assume that they are independent of the surfactant concentration, and this assumption seems to be confirmed by the experimental data. It thus seems reasonable to conclude that the distribution coefficient is independent of surfactant concentration, at least over a moderate range and at low alcohol contents. Thus, the data in Tables 6.2 and 6.3 are valid at any surfactant concentration, at least up to about 0.3 M. 

Complexes in molten salts, variation with concentration, ofUgand, 7(X)... 

Equivalent conductivity and concentration, 434 of dilute solutions, tabulated, 435 function of rate processes, 467 at infinite dilution, 438 variation with concentration, diagiammated and tabulated, 437 in terms of mobilities, 447... 

Surface Absorption Coefficients Variation with Concentration of Dissolved SaltsT This aspect of the investigation attempted to determine the effect of dissolved salts, which may be present in natural ground waters, on the surface absorption coefficient, k, defined as ... 

Let us return now to the values of a that have already been used for the calculation, and to their variation with concentration and temperature. As it is usual to adopt constant values of a for each salt, these values do not... 

Figure 3.35 Effect of recirculation rate (cross-flow velocity) on flux variation with concentration.

The electrical conductances of solutions of mercurous salts resemble closely, in magnitude and variation with concentration, the conductances of uni-divalent rather than uni-univalent electrolytes. 

---