Define Eยฐ<sub>cell</sub>.
Cell potential under standard conditions (298.15 K, 1 atm, 1 M concentrations).
Define E<sub>cell</sub>.
Cell potential under non-standard conditions.
Define the reaction quotient, Q.
A measure of the relative amount of products and reactants present in a reaction at a given time. Used to determine if a reaction is at equilibrium.
Define Faraday's constant (F).
The charge of one mole of electrons, approximately 96485 C/mol e-.
Define 'n' in the Nernst Equation.
Moles of electrons transferred in the balanced redox reaction.
How to determine Q for the reaction: $2Al(s) + 3Mn^{2+}(aq) \rightarrow 2Al^{3+}(aq) + 3Mn(s)$?
Q = $\frac{[Al^{3+}]^2}{[Mn^{2+}]^3}$
Steps to predict E<sub>cell</sub> relative to Eยฐ<sub>cell</sub> using Q.
1. Calculate Q. 2. If Q > 1, E<sub>cell</sub> < Eยฐ<sub>cell</sub>. 3. If Q < 1, E<sub>cell</sub> > Eยฐ<sub>cell</sub>.
How do you calculate Eยฐ<sub>cell</sub> at equilibrium using the Nernst Equation?
Set E<sub>cell</sub> = 0 and Q = K in the Nernst Equation, then solve for Eยฐ<sub>cell</sub>.
What is the formula of Nernst Equation?
$E_{cell} = E^circ_{cell} - \frac{RT}{nF}lnQ$ or $E_{cell} = E^circ_{cell} - \frac{0.0592}{n}logQ$
How to relate ฮG to E<sub>cell</sub>?
ฮG = -nFE<sub>cell</sub>
Differentiate between Eยฐ<sub>cell</sub> and E<sub>cell</sub>.
Eยฐ<sub>cell</sub>: Cell potential at standard conditions. | E<sub>cell</sub>: Cell potential at non-standard conditions.
Compare the conditions when Q = 1 versus Q โ 1.
Q = 1: Standard conditions, all concentrations are 1 M. | Q โ 1: Non-standard conditions, concentrations are not 1 M.
How does Q relate to K at equilibrium and non-equilibrium?
At equilibrium: Q = K. | Non-equilibrium: Q โ K.
What is the difference between a voltaic cell at equilibrium and non-equilibrium?
Non-equilibrium: Running galvanic cell, E<sub>cell</sub> > 0. | Equilibrium: Dead battery, E<sub>cell</sub> = 0.
Compare the effect of Q > 1 and Q < 1 on E<sub>cell</sub>.
Q > 1: E<sub>cell</sub> < Eยฐ<sub>cell</sub>. | Q < 1: E<sub>cell</sub> > Eยฐ<sub>cell</sub>.