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Thermodynamics equation for

In the late eighteenth century Priestley prepared ammonia by reacting HN03(g) with hydrogen gas. The thermodynamic equation for the reaction is... [Pg.221]

We have seen how to calculate q for the isochoric and isobaric processes. We indicated in Chapter 1 that q = 0 for an adiabatic process (by definition). For an isothermal process, the calculation of q requires the application of other thermodynamic equations. For example, q can be obtained from equation (2.3) if AC and w can be calculated. The result is... [Pg.56]

Note that we have also specified these equilibrium constants in terms of the activity of the associated defects. We can also write thermodynamic equations for these defects ... [Pg.102]

By virtue of the function (3.6), concentrations, which are readify determined parameters, can be used instead of chemical potentials in the thermodynamic equations for ideal systems. The simple connection between the concentrations and chemical potentials is lost in real systems. To facilitate the changeover from ideal to nonideal systems and to avoid the use of two different sets of equations in chemical thermodynamics,... [Pg.38]

In electrolyte solutions, nonideality of the system is much more pronounced than in solutions with uncharged species. This can be seen in particular from the fact that electrolyte solutions start to depart from an ideal state at lower concentrations. Hence, activities are always used in the thermodynamic equations for these solutions. It is in isolated instances only, when these equations are combined with other equations involving the number of ions per unit volume (e.g., equations for the balance of charges), that concentrations must be used and some error thus is introduced. [Pg.39]

The overall thermodynamic equation for ozone conversion to oxygen is... [Pg.70]

The energy storage and power characteristics of electrochemical energy conversion systems follow directly from the thermodynamic and kinetic formulations for chemical reactions as adapted to electrochemical reactions. First, the basic thermodynamic considerations are treated. The basic thermodynamic equations for a reversible electrochemical transformation are given as... [Pg.9]

Two main approaches can be taken when developing thermodynamic equations for the correlation and prediction of equilibrium data. Both are semiempirical in that they are based on simplifications of rigorous thermodynamic expressions, but include parameters that have to be fitted to... [Pg.423]

Katchalsky and Curran W formulated the nonequilibrium thermodynamic equations for the transport of material through a discontinuous membrane. However, there was a difficulty in their expressions, as they required the "average concentration" in the membrane. In order to overcome this difficulty of evaluating the... [Pg.253]

A statistical thermodynamic equation for gas adsorption on synthetic zeolites is derived using solid solution theory. Both adsorbate-adsorbate and adsorbate-adsorbent interactions are calculated and used as parameters in the equation. Adsorption isotherms are calculated for argon, nitrogen, ammonia, and nitrous oxide. The solution equation appears valid for a wide range of gas adsorption on zeolites. [Pg.25]

The thermodynamic equations for the Gibbs energy, enthalpy, entropy, and chemical potential of pure liquids and solids, and for liquid and solid solutions, are developed in this chapter. The methods used and the equations developed are identical for both pure liquids and solids, and for liquid and solid solutions therefore, no distinction between these two states of aggregation is made. The basic concepts are the same as those for gases, but somewhat different methods are used between no single or common equation of state that is applicable to most liquids and solids has so far been developed. The thermodynamic relations for both single-component and multicomponent systems are developed. [Pg.159]

The thermodynamic approach applied here considers the adsorbent plus the adsorbed gas, or vapor, as a solid solution (system aA). Applying this description, it is feasible to get the fundamental thermodynamic equation for the aA system [2,15,16,25]... [Pg.284]

The fundamental thermodynamic equation for a reversible electrochemical transformation is... [Pg.392]

Equation (8) constitutes the basic thermodynamic equation for the calculation of the radius of the globules. Of course, explicit expressions, in terms of the radius of the globules and volume fraction, are needed fort, C and af before such a calculation can be carried out. Expressions for Af will be provided in another section of the paper, but it is difficult to derive expressions fory and C. One may, however, note that y (and also C) depends on the radius for the following two reasons (1) its value depends upon the concentrations of surfactant and cosurfactant in the bulk phases, which, because the system is closed, depend upon the amounts adsorbed on the area of the internal interface of the microemulsion (2) in addition to the above mass balance effect, there is a curvature effect on y (this point is examined later in the paper). [Pg.253]

Lucchelli, E. Tomka, I. Vancso, G. Yeh, P. L., "Numerical Evaluation of the Thermodynamic Equation for the State of Polymer Melts from Pressure-Volume-Temperature (PVT) Data," Polym. Bull., 20, 569 (1988). [Pg.176]

Charles M. Hansen (4) was working in the area of paint technology. He was aware oT the Hildebrand/Scott solubility parameter, and explored the use of the solubility parameter in polymer-solvent interactions. He began his research with the consideration of the thermodynamic equation for the energy of mixing... [Pg.122]

Linear viscoelastic behavior is actually observed with polymers only in very restricted circumstances involving homogeneous, isotropic, amorphous specimens subjected to small strains at temperatures near or above Tg and under test conditions that are far removed from those in which the sample may be broken. Linear viscoelasticity theory is of limited use in predicting service behavior of polymeric articles, because such applications often involve large strains, anisotropic objects, fracture phenomena, and other effects which result in nonlinear behavior. The theory is nevertheless valuable as a reference frame for a wide range of applications, just as the thermodynamic equations for ideal solutions help organize the observed behavior of real solutions. [Pg.410]

We begin with the application of the first law of thennodynanucs first to a dosed system and then to an open system. A system is any bounded portion of the universe, moving or stationary, which is chosen for the application of the various thermodynamic equations. For a closed system, in wMch no mass... [Pg.505]

Thermodynamic equations. For any change of state we have, by the first law,... [Pg.149]

Additionally, there are other scale-up effects that are not addressed by the thermodynamic equations for drying. Variations in the heat loss to attendant ductwork of the different scale dryers will be apparent, as will attrition variations between the different scale batches. The adhesiveness of the material being dried, including resultant static charges and temperature induced agglomeration, may alter the product quality upon scale-up and require other approaches to overcome these issues. [Pg.3199]

The quantities dEfdrii)s y 2 (dEldri2)s,y,ni are defined as the chemical potentials, and of species 1 and 2, respectively. These chemical potentials depend on the composition of the solution, that is, the mole fractions, Xj and Xj. Comparing equations 32 and 19, we note that T = (dE/dS)y j and p = dEldV)s j. The fundamental chemical thermodynamic equation for a binary solution can then be written as... [Pg.30]

A chemical reaction produces a variation in the mole numbers of a closed solution, dui = Vi d, where the v, are the stoichiometric coefficients of Ihe species in the reaction (< 0 for reactants, > 0 for products) and is the advancement variable (> 0). For example, a weak acid, HA, dissociates in aqueous solution according to the reaction HA + H2O = H30 + A , and the respective stoichiometric coefficents are — 1, — 1, and +1, and +1. I he fundamental chemical thermodynamic equation for this reaction is then... [Pg.30]

The paH (which can also be termed the pa or the pfi) is a practical unit consistent both with the experimental methods for pH measurements and with the thermodynamic equations for acid-base equilibria in the solvents concerned, but it should be noted that paH is a succession of scales rather than a single, universal scale of acidity. Consequently, two solutions in different solvent media may have the same paH but behave in totally different ways in acid-base reactions. [Pg.100]

The thermodynamic equations for ideal solutions are derived by considering the equilibrium between a given component in the vapor phase and liquid solution. Thus, for component A in a solution containing two components,... [Pg.16]

Derivation of the thermodynamic equations for an electrolyte system with ion pairing follows the same procedure given for a weak electrolyte. However, in the following the ion pairing equilibrium is defined in terms of an association process. For a 1-1 electrolyte, ion pairing is described as... [Pg.136]

These definitions can be easily incorporated into a computer program which will generate the appropriate coupled spin states and energies, and then used to calculate the magnetic susceptibility under Van Vleck s equation (11). The more complete thermodynamic equation for X is given in Eq. (12). [Pg.268]


See other pages where Thermodynamics equation for is mentioned: [Pg.506]    [Pg.82]    [Pg.41]    [Pg.233]    [Pg.75]    [Pg.78]    [Pg.171]    [Pg.178]    [Pg.71]    [Pg.333]    [Pg.177]    [Pg.52]    [Pg.364]    [Pg.127]    [Pg.658]    [Pg.290]    [Pg.427]    [Pg.31]    [Pg.385]    [Pg.136]    [Pg.59]    [Pg.293]   
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Thermodynamic equations

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