Gibbs Free Energy and Spontaneity


In my previous couple of blog posts, I talked about a thermodynamic state function called enthalpy, and how it is used by scientists and engineers. This included covering a principle called Hess’s Law, which has led to the tabulation of enthalpy values for certain reactions under a set of standardized conditions, such that the idea could be generalized to make thermodynamic predictions about a huge variety of processes.

Those posts laid the groundwork for the following topic.  (more…)


State Functions, Entropy, Path Dependence, and Energy Conservation in Thermodynamic Systems

State Functions vs Path Dependent Functions

In thermodynamics, scientists distinguish between what are called state functions vs path functions. State functions are properties of a system whose values do not depend on how they were arrived at from a prior state of the system. They depend only on the starting and ending states of the system. On the other hand, path functions can take on very different values depending on the path by which the system arrived at a state from its previous state. (more…)