Time-dependence in homogeneous catalysis. 2. The general actions of time-dependent ("mechanical") and energy-Dependent ("thermodynamic") catalysts

[extract] 6.1 INTRODUCTION

In Chapter 1, we described two fundamental types of action that are observed in

physical science. The first is created by the laws of thermodynamics, which describe,

in essence, how changes in energy create actions or set processes in train. Because

the field of thermodynamics today extends far beyond this most elementary description

and to avoid any possible confusion, we have termed actions or processes of this

type energy-dependent in character. An example of an energy-dependent action

is that of a ball falling to Earth under the influence of gravity. The gravitational

field is invisible and intangible. However, it induces movement. We can often only

perceive energy gradients in the physical effect that they create.