CHEM 1202 Chapter : Chapter 19
Document Summary
!g, !h, and !s refer to "products minus reactants" or. "final minus initial" per the usual energy conventions. "constant temperature" merely means that if reaction changes temperature we need to bring it back to original t before making final measurements (review state functions). !g = !h - t!s is operative form of gibbs free energy equation we will use in this course. Any process for which !g is negative is spontaneous (prefers to go in the "forward" direction) and any process for which !g is positive prefers to go in the reverse direction (ie. is nonspontaneous). G is the "instability level" of the system. Nature tries to minimize g by as many different schemes as it can. Each successful scheme reduces g and thereby makes !g (final minus initial) negative. What contributes to instability gain/loss (!g)? contributes: enthalpy (h). Loss of heat (negative !h) from system to process.
