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Theorems of moderation

The effect of external pressure on the rates of liquid phase reactions is normally quite small and, unless one goes to pressures of several hundred atmospheres, the effect is difficult to observe. In terms of the transition state approach to reactions in solution, the equilibrium existing between reactants and activated complexes may be analyzed in terms of Le Chatelier s principle or other theorems of moderation. The concentration of activated complex species (and hence the reaction rate) will be increased by an increase in hydrostatic pressure if the volume of the activated complex is less than the sum of the volumes of the reactant molecules. The rate of reaction will be decreased by an increase in external pressure if the volume of the activated complex molecules is greater than the sum of the volumes of the reactant molecules. For a decrease in external pressure, the opposite would be true. In most cases the rates of liquid phase reactions are enhanced by increased pressure, but there are also many cases where the converse situation prevails. [Pg.219]

Theorem governing the hehavior of perturbed systems are often known as theorems of coouraint or theorems of moderation. The best known thermodynamic theorem of moderation is that ofl.c Chatelier-Braun. which in the form slated hy Le Chamber is... [Pg.926]

Theorems governing the behaviour of perturbed systems are known as theorems of restraint or theorems of moderation. [Pg.262]

A similar theorem can be derived for the condition of volume moderation, by using equations (2.7), (17.6) and (4.41). An adiabatic isothermal system only exhibits volume moderation if... [Pg.265]

This book is the first volume of a Treatise on Thermodynamics based on the methods of Gibbs and De Donder. It deals with the following topics fundamental theorems, homogeneous systems, heterogeneous systems, stability and moderation, equilibrium displacements and equilibrium transformations, solutions, azeotropy, and indifferent states. The second volume deals with surface tension and adsorption while the third and last will be concerned with irreversible phenomena. [Pg.562]

We can obtain an expression for the characteristic numbers Aj in terms of the disadvantage factors by integrating (26) over the moderator and applying Green s theorem to the left side. This gives, since the gradient of Zi vanishes over the cell boundaxy. [Pg.484]

Compared to discrete variables, ctmtinuous variables have a large information content so that small or moderate sample sizes are sufficient for a powerful test The probability distribution of the sample mean should be known and preferably normal, either because the population distribution is normal, or the sample is large enough to let the distribution of the sample mean approach normality (central limit theorem). [Pg.415]


See other pages where Theorems of moderation is mentioned: [Pg.262]    [Pg.266]    [Pg.268]    [Pg.240]    [Pg.262]    [Pg.266]    [Pg.268]    [Pg.240]    [Pg.21]    [Pg.180]    [Pg.30]    [Pg.33]    [Pg.164]    [Pg.609]    [Pg.185]    [Pg.14]    [Pg.179]    [Pg.25]    [Pg.157]    [Pg.65]    [Pg.609]    [Pg.180]    [Pg.143]    [Pg.609]    [Pg.14]    [Pg.139]    [Pg.269]    [Pg.171]    [Pg.417]    [Pg.395]    [Pg.664]    [Pg.656]    [Pg.484]    [Pg.8]    [Pg.40]   
See also in sourсe #XX -- [ Pg.262 , Pg.263 , Pg.264 , Pg.265 , Pg.266 , Pg.267 , Pg.268 ]




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Moder

Moderant

Moderants

Moderates

Moderation

Moderator

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