CHEM 202 Chapter Notes - Chapter 45: Gibbs Free Energy, Joule
Document Summary
In chemistry, spontaneous gets a subtly different definition: spontaneous means can happen by itself under the given conditions . It refers to the capability to occur and not to whether it does occur. If a reaction does not occur by itself, then it is nonspontaneous: spontaneous=allowed process, nonspontaneous=not allowed process. Review on system and surrounding: the system is the sample under study. The surrounding are the environment of the sample: universe=system + surroundings, total=system + surroundings, conservation of energy: the total j"s b/t the system and the surroundings stay the same. Distinction b/t h and s: the j"s of enthalpy ( h) are always conserved, but the j/k units of entropy ( s) will not be conserved while any reaction or process is occurring. If the reaction would instead result in a decrease in s univ, which amounts to a negative suniv, then it cannot happen by itself under the given conditions: transfer of heat causes change in entropy: