G
1. Three important terms relating to the free energy change of a process are:
- the total free energy change for a reaction under any conditions
- free energy under standard conditions (all concentrations of 1M)
, the free energy change under standard biological conditions (all concentrations 1M, [H2O] = constant, and pH = 7.0)
Thus, a positive may influence
a reaction, but cellular conditions may make the overall for the reaction negative.
2. and only
determines whether a reaction is favorable
as written.. Only when is negative
is a reaction favored. The sign of or does not determine the direction a reaction will
proceed.
3. depends
on temperature ( = 
H - TS). This can be a factor for a given
reaction occurring in different organisms living under very different
conditions of temperature.