Free energy and Chemical Energy question

[gkangelexa]

\DeltaG = -n F Emax

and

\DeltaG = \DeltaG\circ + RT ln(Q)


When do we use the first equation and when do we use the second one?

[Mike H]

The first equation contains the Faraday constant. What sorts of chemical systems/problems would entail needing to use that?

What do the two terms on the right-hand side of the second equation represent?