Lecture 4 Gibbs Energy and Cell Potential Flashcards
equation for electrical work done
Welec = -Q X V
charge = Q
potential difference = V
why is electrical work done negative
because the system loses energy as it does work
equation for charge of one mol of electrons
F = e X Na
= 96485Cmol^-1
equation for total charge of a reaction
with z mols of electrons
Q = z F
equation for the maximum work done of an electrochemical cell
Welec = - z F * Ecell
equation for gibbs energy of an electrochemical cell
deltarG = - z F * Ecell
when is maximum work done thermodynamically
under reversible conditions
very small current
large resistance
gibbs free energy relation to thermodynamic equilibrium constant
deltarG = -RT ln K
at standard conditions
what values of equilibrium constant means reaction goes to completion
large positive values
equation for gibbs energy under any conditions
deltarG = deltarG standard conditions + RTlnQ
where Q is reaction quotient
equation for reaction quotient
Q = capital pi (a products) ^v products/ capital pi (a reactants)^ v reactants
what is nerst equation
Ecell standard conditions - RT/zF lnQ
what is capital pi for
product all the individual ones
when is a battery flat
when the reaction reaches equilibrium
