Surface Tension table

Temperature and molecular weight have a significant effect on surface tension (Table 2.3). For example, in the normal hydrocarbon series, a rise in temperature leads to a decrease in the surface tension, but an increase in molecular weight increases the surface tension. A similar trend, that is, an increase in molecular weight causing an increase in surface tension, also occurs in the acrylic series and, to a lesser extent, in the alkylbenzene series. 

Hogness,1 Burdon,2 Bircumshaw, and Sauerwald have done a great deal to render accurate measurements possible the best method is probably the maximum bubble pressure method, but the measurement of sessile drops (see Chap. IX), and of drop volumes, are also useful. Metals always have a very high surface tension. Table X gives typical results. 

Other physical properties of relevance to the use of R-134a as a solvent are viscosity and surface tension (Table I). In comparison to the conventional liquid solvents, R-134a has both low viscosity and low surface tension, promoting rapid solvent wetting and penetration of a solute matrix. 

It is possible, from the estimates obtained, to proceed to evaluate the interaction parameters for the systems considered. For this. Equation 19 is employed, and the results are also given in Table V. The trend of estimated solid-liquid interfacial tensions for the series of five liquids on each of the solids is roughly parallel to the trend of liquid surface tensions (Table I). Hence, the similar trends found for the interaction parameters on each of the solids are to be expected. 

FIGURE 4.2 Plot of the surface tension a vs. the concentration of SDS, c, , for 11 fixed NaCl concentrations. The symbols are experimental data by Tajima et al. [40,42,43]. The lines represent the best fit [42] with the full set of equations specified in the text, involving the van der Waals isotherms of adsorption and surface tension (Table 4.2). 

For an adhesive to wet a sohd surface, the adhesive should have a lower surface tension than the solid s critical surface tension. Tables 7.2 and 7.3 hst surface tensions of common adherends and liquids. 

Parachors (P ) [Eq. (63)] and molar volumes [Eq. (47)] were used to estimate surface tensions (y). Equation (63) divided by Eq. (47) gave an expression [Eq. (64)] that was used to estimate amorphous poly(l-olefin) surface tensions (Table 16) ... 

The critical surface tension of Teflon is extremely low. In fact Teflon is one of the materials having among the lowest critical surface tensions (Table 6.1). Thus, Teflon is very difflcult to wet by ordinary liquids, most of which have surface tensions above 20 mN m . The wetting can be improved either by using surfactants that can lower substantially the surface tension of liquids or by special surface treatment which can increase the surface tension of Teflon, e.g. by adding polar groups, plasma treatment, etc. 

Let us now evaluate the surface properties of the mixed system formed by whole casein and Tween 20 also shown in Figure 10.4. Despite having similar surface tensions (Table 10.1), the structural... 

A liquid of density 2.0 g/cm forms a meniscus of shape corresponding to /3 = 80 in a metal capillary tube with which the contact angle is 30°. The capillary rise is 0.063 cm. Calculate the surface tension of the liquid and the radius of the capillary, using Table II-l. 

Estimate the surface tension of n-decane at 20°C using Eq. 11-39 and data in Table II-4. 

Inspection of Table III-l shows that there is a wide range of surface tension and E values. It is more instructive, however, to compare E values calculated on an energy per mole basis. The area per mole of spherical molecules of molecular weight M and radius r is... 

The data in Table III-2 have been determined for the surface tension of isooctane-benzene solutions at 30°C. Calculate Ff, F, F, and F for various concentrations and plot these quantities versus the mole fraction of the solution. Assume ideal solutions. 

Some data obtained by Nicholas et al. [150] are given in Table III-3, for the surface tension of mercury at 25°C in contact with various pressures of water vapor. Calculate the adsorption isotherm for water on mercury, and plot it as F versus P. 

The uncertainties in choice of potential function and in how to approximate the surface distortion contribution combine to make the calculated surface energies of ionic crystals rather uncertain. Some results are given in Table VII-2, but comparison between the various references cited will yield major discrepancies. Experimental verification is difficult (see Section VII-5). Qualitatively, one expects the surface energy of a solid to be distinctly higher than the surface tension of the liquid and, for example, the value of 212 ergs/cm for (100)... 

Surface Stresses and Edge Energies. Some surface tension values, that is, values of the surface stress t, are included in Table VII-2. These are obtained by applying Eq. Vll-5 to the appropriate lattice sums. The calculation is very sensitive to the form of the lattice potential. Earlier calculations have given widely different results, including negative r [43, 51, 52]. 

Tables of single substance surface tensions y can be built up tlirough tire measurement of contact angles [134] a few examples are collected in table C2.14.1. These can be combined pairwise according to ...

Table C2.14.1 Single substance macroscopic surface tensions/(mJ m ) of various materials (data mostly from...

Table 5.16 Viscosity and Surface Tension of Various Organic Substances 5.90...

Table 5.18 Viscosity, Dielectric Constant, Dipole Moment, and Surface Tension...

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