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Electrical molar

The salts had a high electrical conductivity, and it was claimed that the values of the molar conductances at infinite dilution showed the formation of a binary and ternary electrolyte respectively. [Pg.14]

The systems of interest in chemical technology are usually comprised of fluids not appreciably influenced by surface, gravitational, electrical, or magnetic effects. For such homogeneous fluids, molar or specific volume, V, is observed to be a function of temperature, T, pressure, P, and composition. This observation leads to the basic postulate that macroscopic properties of homogeneous PPIT systems at internal equiUbrium can be expressed as functions of temperature, pressure, and composition only. Thus the internal energy and the entropy are functions of temperature, pressure, and composition. These molar or unit mass properties, represented by the symbols U, and S, are independent of system size and are intensive. Total system properties, J and S do depend on system size and are extensive. Thus, if the system contains n moles of fluid, = nAf, where Af is a molar property. Temperature... [Pg.486]

The driving force for the transport of all particles is a change in the electrochemical potential /i, which is related to the partial molar free enthalpy /i, and the electric potential 0 as follows ... [Pg.37]

It is important to realise that whilst complete dissociation occurs with strong electrolytes in aqueous solution, this does not mean that the effective concentrations of the ions are identical with their molar concentrations in any solution of the electrolyte if this were the case the variation of the osmotic properties of the solution with dilution could not be accounted for. The variation of colligative, e.g. osmotic, properties with dilution is ascribed to changes in the activity of the ions these are dependent upon the electrical forces between the ions. Expressions for the variations of the activity or of related quantities, applicable to dilute solutions, have also been deduced by the Debye-Hiickel theory. Further consideration of the concept of activity follows in Section 2.5. [Pg.23]

The amounts of different substances liberated or dissolved by the same quantity of electricity are proportional to their relative atomic (or molar) masses divided by the number of electrons involved in the respective electrode... [Pg.503]

At salt concentration below those shown in Fig. 5, molar conductivity behavior has been identified with the formation of electrically neutral ion pairs [8]. Between concentration of 0.01 and 0.1 mol L 1 (up to an 0 M ratio of -50 1) the molar conductivity rises and this can be explained by the formation of mobile... [Pg.510]

Cathode material Electroactive substance Reaction potential — E (V) Electrical yield (%) benzene (molar yield) (%) aniline (molar yield) (%) 1,4-cyclo-hexadiene (molar yield ) (%)... [Pg.1008]

The polymerization of cyclic low-molar-mass polycarbonates, polyarylates, and PBT to high-molar-mass thermoplastics has been extensively studied by the General Electric Company during the last decade.57,58 Due to very low viscosity, cyclic oligoesters can be processed like thermosetting resins but retain thermoplastic properties in the final state, after polymerization in the presence of suitable... [Pg.31]

J.9 You are asked to identify compound X, which was extracted from a plant seized by customs inspectors. You run a number of tests and collect the following data. Compound X is a white, crystalline solid. An aqueous solution of X turns litmus red and conducts electricity poorly, even when X is present at appreciable concentrations. When you add sodium hydroxide to the solution a reaction takes place. A solution of the products of the reaction conducts electricity well. An elemental analysis of X shows that the mass percentage composition of the compound is 26.68% C and 2.239% H, with the remainder being oxygen. A mass spectrum of X yields a molar mass of 90.0 g-moF. (a) Write the empirical formula of X. (b) Write... [Pg.101]

Besides these special physical properties, hydrogen-bonded liquid water also has unique solvent and solution properties. One feature is high proton (H ) mobility due to the ability of individual hydrogen nuclei to jump from one water molecule to the next. Recalling that at temperatures of about 300 K, the molar concentration in pure water of H3O ions is ca. 10 M, the "extra" proton can come from either of two water molecules. This freedom of to transfer from one to an adjacent "parent" molecule allows relatively high electrical conductivity. A proton added at one point in an aqueous solution causes a domino effect, because the initiating proton has only a short distance to travel to cause one to pop out somewhere else. [Pg.111]

Table 1.2 Aspects of dioxygen gas at the molar, molecular and electrical (intramolecular) levels of discourse. Taken from Jensen (1998b). (Jensen s use of the term molar level eorresponds with the more common macroscopic level.)... Table 1.2 Aspects of dioxygen gas at the molar, molecular and electrical (intramolecular) levels of discourse. Taken from Jensen (1998b). (Jensen s use of the term molar level eorresponds with the more common macroscopic level.)...
The linear polarizability, a, describes the first-order response of the dipole moment with respect to external electric fields. The polarizability of a solute can be related to the dielectric constant of the solution through Debye s equation and molar refractivity through the Clausius-Mosotti equation [1], Together with the dipole moment, a dominates the intermolecular forces such as the van der Waals interactions, while its variations upon vibration determine the Raman activities. Although a corresponds to the linear response of the dipole moment, it is the first quantity of interest in nonlinear optics (NLO) and particularly for the deduction of stracture-property relationships and for the design of new... [Pg.95]

The relationship between the diffusional flux, i.e., the molar flow rate per unit area, and concentration gradient was first postulated by Pick [116], based upon analogy to heat conduction Fourier [121] and electrical conduction (Ohm), and later extended using a number of different approaches, including irreversible thermodynamics [92] and kinetic theory [162], Pick s law states that the diffusion flux is proportional to the concentration gradient through... [Pg.562]

Just as each element has a characteristic molar mass, so does every chemical compound. Chemical compounds are composed of atoms bound together into molecules or ions clustered together in electrically neutral aggregates. In either case a chemical formula describes the atomic composition of a compound. [Pg.148]

C03-0092. A chemist places 3.25 g of sodium carbonate in a 250.-mL volumetric flask and fills it to the mark with water, (a) Calculate the molarities of the major ionic species, (b) Draw a molecular picture that shows a portion of this solution, making sure the portion is electrically neutral. [Pg.191]

C06-0071. An electric heater adds 19.75 kJ of heat to a constant-volume calorimeter. The temperature of the calorimeter increases by 4.22 °C. When 1.75 g of methanol is burned in the same calorimeter, the temperature increases by 8.47 °C. Calculate the molar energy of combustion of methanol. [Pg.424]

Electricity is normally measured in units of charge, the coulomb (C), or as rate of electrical current flow, the ampere (A 1 A — 1 C/. ). The total amount of charge is the product of the current flow, symbolized by I, and the time for which this current flows Charge = It Just as molar mass provides the link between mass and moles, the Faraday constant provides the link between charge and moles. The number of moles of electrons transferred in a specific amount of time is the charge in coulombs divided by the charge per mole, F ... [Pg.1397]

Enzyme UE/mg Optimum pH Iso-electric point Molar mass... [Pg.972]

Danek and his group have independently proposed a quite similar model, which they call the dissociation modeV - For this model Olteanu and Pavel have presented a versatile numerical method and its computing program. However, they calculated only the electrical conductivity or the molar conductivity of the mixtures, and the deviation of the internal mobilities of the constituting cations from the experimental data is consequently vague. [Pg.149]

Debye and Falkenhagen predicted that the ionic atmosphere would not be able to adopt an asymmetric configuration corresponding to a moving central ion if the ion were oscillating in response to an applied electrical field and if the frequency of the applied field were comparable to the reciprocal of the relaxation time of the ionic atmosphere. This was found to be the case at frequencies over 5 MHz where the molar conductivity approaches a value somewhat higher than A0. This increase of conductivity is caused by the disappearance of the time-of-relaxation effect, while the electrophoretic effect remains in full force. [Pg.111]

When the adsorbed components are electrically charged, then the partial molar Gibbs energy of the charged component depends on the charge of the given phase, and thus the chemical potentials in the above relationships must be replaced by the electrochemical potentials. The Gibbs adsorption isotherm then has the form... [Pg.217]


See other pages where Electrical molar is mentioned: [Pg.835]    [Pg.127]    [Pg.274]    [Pg.533]    [Pg.44]    [Pg.466]    [Pg.349]    [Pg.191]    [Pg.91]    [Pg.958]    [Pg.962]    [Pg.7]    [Pg.560]    [Pg.560]    [Pg.596]    [Pg.646]    [Pg.384]    [Pg.1390]    [Pg.44]    [Pg.130]    [Pg.775]    [Pg.13]    [Pg.96]    [Pg.102]    [Pg.582]   
See also in sourсe #XX -- [ Pg.28 ]




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