Free energy, molar

Molar free energy Molar free energy of A... 

G = Gibbs molar free energy S = molar entropy F = Helmholtz free molar energy H = molar enthalpy U = molar internal energy... 

Gy = molar free energy of the liquid G = molar free energy of the gas... 

Gibbs free energy or Gibbs molar free energy molar flow of gas phase acceleration of gravity enthalpy, molar enthalpy, weight enthalpy Henry s constant Planck s constant height horsepower radiation intensity molar flux... 

The total free energy of the system is then made up of the molar free energy times the total number of moles of the liquid plus G, the surface free energy per unit area, times the total surface area. Thus... 

A very important thermodynamic relationship is that giving the effect of surface curvature on the molar free energy of a substance. This is perhaps best understood in terms of the pressure drop AP across an interface, as given by Young and Laplace in Eq. II-7. From thermodynamics, the effect of a change in mechanical pressure at constant temperature on the molar h ee energy of a substance is... 

The standard molar free energy change upon adsorption of the probe gas is thus given by... 

The dependence of the rate constant on pressure provides another activation parameter of mechanistic utility. From thermodynamics we have (dGldP)T = V, where V is the molar volume (partial molar volume in solutions). We define the free energy of activation by AG = G — SGr. where SGr is the sum of the molar free energies of the reactants. Thus, we obtain... 

The energy of a system can be changed by means of thermal energy or work energy, but a further possibility is to add or subtract moles of various substances to or from the system. The free energy of a pure substance depends upon its chemical nature, its quantity (AG is an extensive property), its state (solid, liquid or gas), and temperature and pressure. Gibbs called the partial molar free heat content (free energy) of the component of a system its chemical potential... 

If only one mole of the gas is considered, the quantity G is called the chemical potential, /x, or the partial molar free energy. In this case n = 1, and equation 20.197 becomes... 

Equations for the Standard Free Energy of Formation and Partial Molar Free Energies of Atomic Oxygen for Plutonium Oxides (1600-2150 K), cal/mol... 

These expressions comprise the nonideal terms in the previous equations for the chemical potential, Eqs. (30) and (31 ). They may therefore be regarded as the excess relative partial molar free energy, or chemical potential, frequently used in the treatment of solutions of nonelectrolytesi.e, the chemical potential in excess (algebraically) of the ideal contribution, which is —RTV2/M in dilute solutions. 

Mu M2, Ma , Chemical potential (i.e., partial molar free energy) of solvent, polymer (all species collectively), x-mer, and a polymer unit, respectively. 

A borehole stability model has been developed that takes into account both the mechanical and the chemical aspects of interactions between drilling fluid and shale [1231]. Chemically induced stress alteration based on the thermodynamics of differences in water molar free energies of the drilling fluid and shale is combined with mechanically induced stress. Based on this model, it should be possible to obtain the optimal mud weight and salt concentration for drilling fluids. 

The behaviour of most metallurgically important solutions could be described by certain simple laws. These laws and several other pertinent aspects of solution behaviour are described in this section. The laws of Raoult, Henry and Sievert are presented first. Next, certain parameters such as activity, activity coefficient, chemical potential, and relative partial and integral molar free energies, which are essential for thermodynamic detailing of solution behaviour, are defined. This is followed by a discussion on the Gibbs-Duhem equation and ideal and nonideal solutions. The special case of nonideal solutions, termed as a regular solution, is then presented wherein the concept of excess thermodynamic functions has been used. 

The terms GA and GB are formally defined as the partial molar free energies of A and B respectively in the solution. 

One must recognize that the partial molar free energy is not a measurable quantity because the absolute value of the free energy is not measurable. However, the relative partial molar free energy, AGa, defined as follows, is measurable... 

Besides the partial molar and the relative partial molar free energies of the components, some other important thermodynamic properties are the partial molar and the relative partial molar enthalpies and entropies. The partial molar enthalpy and entropy of the component A are defined by... 

The relative partial molar free energy of A is written in terms of the integral molar free energy of the solution as... 

When the formation of one mole of the solution is considered, the integral molar free energy of mixing, AGM, is given by... 

The equality of aA and PA/PA has been explained earlier. It may be recalled that the activity of the component A in the solution is defined by this equality. For the binary solution A-B, the integral molar free energy of mixing is then... 

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