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Temperature, absolute equilibrium

AH = latent heat of transformation = equilibrium temperature (absolute). [Pg.372]

Tantalum, oxidation number, 414 "Teflon, 347 Tehachapi mountains, 132 Tejon pass, 132 Television picture tube, 409 Temperature absolute, 57 absolute zero, 58 earth s center, 440 effect on equilibrium, 67, 148,167 on gas volume, 57 on rate, /29 on K,r, 181... [Pg.466]

K is the temperature dependent equilibrium constant T is the absolute temperature in degrees Kelvin and B, C, D, and E are constants. Numerical values of these constants are presented in Table 2. [Pg.93]

As can be seen, the alcohol autocomplexes possess the highest strength the bond strength in the series of amine complexes with alcohol falls from the primary to the tertiary ones, which proves the decisive role of steric factors in the formation of H-complexes with amines. At low temperatures, the equilibrium constant of the A H complexes falls in the series Keql > Keq 2 > Keq3 however, at temperatures over 6Q-70 °C the series becomes reversed. It means that during the reaction at elevated temperatures not only the absolute but also the relative concentrations of the A2H... [Pg.120]

Anisothermal Transport Across a Phase Boundary. Once we know the effect of temperature on equilibrium position, we need know only its effects on diffusivities and the condensation coefficient to complete our task. The Stephan-Maxwell equation states that diffusivity in the vapor increases with the square root of the absolute temperature. In the condensed phase the temperature effect is expressed by an Arrhenius-type equation. [Pg.19]

Owing to this activation threshold, the first precipitation product from aqueous solutions of silicic acids will be an amorphous silica of some degree of hydration, while at room temperature the growth of vitreous and crystalline forms of silica from the precipitate (and thus the approach toward the absolute equilibrium) will proceed extremely slowly. With this understanding the data in Figure 1 are said to represent, an equilibrium—i.e., the reversible equilibrium between silicic acids in aqueous solution and metastable hydrated silica or polymeric silicic acid as precipitate. [Pg.169]

A sequence of wafers was polished for a duration adequate to ensure the attainment of thermal stability. The final or equilibrium temperature could then be plotted against the equilibrium removal rate. In the spirit of treating CMP like a chemical reaction, we can plot log of equilibrium removal rate vs. inverse absolute equilibrium (instantaneous) temperature. We have done so for the standard, two-component slurry, the abrasive alone and the oxidizer alone, in Fig. 2, below. Note that each of the three sequences results in a straight line when plotted in this manner, and that moreover, the slopes of the three lines are very similar. The implication of the straight line fits (except near room temperature for the standard slurry) and the similar slopes is that the polish rate obeys an Arrhenius relationship, and that the activation energy is similar for the slurry and each of its components, differing only in the fi"equency factor constant. Further, that while the rate for a given slurry proceeds like a chemical reaction, efficacious removal is achieved only with a combination of oxidizer and abrasive. [Pg.157]

At complete ionization of the hydrogen (e.g. when added to a plasma with another gas as the main constituent) ne = p/(2 x k x Te) has a maximum at a wavelength of X — (7.2 x 107)/Te or at a fixed wavelength, the maximum intensity is found at a temperature Te = (5.76 x 107)/2. Thus, the electron temperature can be determined from the wavelength dependence of the continuum intensity. As Te is the electron temperature, absolute measurements of the background continuum emission in a plasma, e.g. for the case of hydrogen, allow determination of the electron temperature in a plasma, irrespective of whether it is in local thermal equilibrium or not. Similar methods also make use of the recombination continuum and of the ratio of the Bremsstrahlung and the recombination continuum. [Pg.18]

Crystallizer Absolute Pressure (mm Hg) Crystallizer Temperature c Equilibrium Solubility Mass Ratio of Dissolved Solute per Unit Mass of Solvent... [Pg.622]

Gas-phase metal-ligand bond energies can be measured by a variety of experimental techniques. Measurements of absolute values can be made by temperature-dependent equilibrium methods, " " blackbody infrared radiative dissociation (BIRD), " radiative association, " and the TCID method discussed in detail here. Measurements of relative thermochemistry can be accomplished using equilibrium methods, the kinetic method, " and competitive CID (see Section 2.12.5.7). This review cannot include the details of all such measurements. [Pg.150]

Figure 9.5 (a) The % relative humidity established by saturated solutions of four different salts as a function of temperature. The circles indicate the equilibrium temperature for reaction (9.18) at the indicated % RH. (b) The % RH values from (a) converted to In/f and plotted versus the inverse absolute equilibrium temperature. From this plot, values of A G° and A H° for reaction (9.18) may be obtained. The line is a least-squares fit to the data, and is shown as the dashed line in (a). [Pg.249]

As each conserved state determines a domain, additional connection constraints can be found for various port types. For instance, a bond connected to one side of a 0-junction may be connected to a C-type storage port or a source port, as these ports do not violate the balance equation. However, in principle, one should be more careful when connecting an I-type, R-type, TF-type, or GY-typeport, because these ports cannot absorb the conserved state related to the flow. However, all domains with relative equilibrium-determining variables have a non-displayed balance for the reference node (this balance equation is dependent on the balance equations for the rest of the network and corresponds to the row that is omitted in an incidence matrix to turn it into a reduced incidence matfix of an electrical circuit, for example). This additional balance compensates for this flow, such that it is still possible to connect these ports without violating the balance equation. Note that the I-type port in principle is a connection to a GY-type port that connects to the storage in another domain. Some domains have absolute equilibrium-determining variables, like temperature and pressure, but since in most cases it is not practical to choose the absolute zero point as a reference, usually another reference state is chosen, such that these variables are treated as differences with respect to an arbitrary reference and an additional balance too. [Pg.50]

The equilibrium constant of the aldolase reaction depends greatly on temperature. At low temperatures the condensation is more favored, whereas the amount of triose at equilibrium increases with rising temperatures. The equilibrium constant is evaluated as (dihydroxyacetone phosphate) (phosphoglyceraldehyde)/(HDP) = IT, = 6 X 10 at 28 C. At first glance it appears that this implies that very little triose exists at equilibrium at this temperature. This is an example of reactions in which one compound is converted to two, and closer examination shows that the percentage conversion in such cases is a function of the absolute concentration. Thus, with 1 M HDP, only a fraction of 1 per cent is split at equilibrium, whereas at 10 M, approximately half is converted to triose phosphates. The equilibrium constant is markedly affected by temperature. Lower temperatures favor the condensation to HDP, while higher temperatures cause the reaction to shift toward increased formation of triose phosphates. [Pg.53]

In Appendix A it is shown that, if Z T) is in the form of Eq. [46], then F (T) is equal to the value of the absolute minimum of the Landau free energy density fF at temperature T. Moreover, the (temperature-dependent) equilibrium value of the order parameter, , is equal to the value of S which minimizes at each T. Therefore, in order to obtain F (T), we differentiate fF with respect to S and set the result equal to zero for S = ... [Pg.166]

In these equations, and p are the chemical potentials of the dye in the solution and in the fibre, respectively, and and o are the respective activities or effective concentrations. and are the standard chemical potentials for the dye in its standard state in the solution and in the fibre, respectively. The standard states are those for which the dye activity in either phase is unity. R is the universal gas constant and T represents the absolute temperature. At equilibrium, = and thus Eqs 2.9a and 2.9b can be derived ... [Pg.40]

AS = entropy change of reaction T = absolute temperature K = equilibrium constant (mass law)... [Pg.706]

The principle of tire unattainability of absolute zero in no way limits one s ingenuity in trying to obtain lower and lower thennodynamic temperatures. The third law, in its statistical interpretation, essentially asserts that the ground quantum level of a system is ultimately non-degenerate, that some energy difference As must exist between states, so that at equilibrium at 0 K the system is certainly in that non-degenerate ground state with zero entropy. However, the As may be very small and temperatures of the order of As/Zr (where k is the Boltzmaim constant, the gas constant per molecule) may be obtainable. [Pg.373]


See other pages where Temperature, absolute equilibrium is mentioned: [Pg.49]    [Pg.55]    [Pg.248]    [Pg.428]    [Pg.1265]    [Pg.212]    [Pg.61]    [Pg.69]    [Pg.138]    [Pg.81]    [Pg.474]    [Pg.637]    [Pg.103]    [Pg.58]    [Pg.238]    [Pg.97]    [Pg.367]    [Pg.514]    [Pg.386]    [Pg.262]    [Pg.58]    [Pg.75]    [Pg.384]    [Pg.1064]    [Pg.418]    [Pg.418]    [Pg.1959]    [Pg.2761]    [Pg.189]    [Pg.499]   
See also in sourсe #XX -- [ Pg.2 , Pg.3 , Pg.15 ]




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Equilibrium temperature

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