11.Electrochemistry

Oxidation (losses electrons) occurs at the anode (on the left) (lower $E_{red}^\circ$)

Reduction (gain electrons) occurs at the cathode (on the right) (higher $E_{red}^\circ$)

Cell diagram for the following cell: , sometimes the cell diafgram is written with spectator ions left out, for example:

In cell diagram, platinum is served as an inactive electrode

The cell is spontanous when $E_{cell}^\circ > 0$

Name	Symbol	Unit
Standard cell potential	$E_{cell}^\circ$	$V$
Oxidation half-cell potential	$E_{ox}^\circ$	$V$
Reduction half-cell potential	$E_{red}^\circ$	$V$
Faraday constant	$F=96485\frac{C}{mol}$	$\frac{C}{mol}$

Equation	Explain
$E=V\times C$	Energy = volt x coulomb
$-nFE_{cell}=\Delta G$	$n$: number of electrons transfered in the cell reaction
$-\Delta G$	maximum electrical that can be done by an electrochemical cell for 1 mol of reaction
$E_{ox}^\circ=-E_{red}^\circ$
$E_{cell}^\circ=E_{red}^\circ(cathode)-E_{red}^\circ(anode)$
$E_{cell}^\circ=\frac{RT}{nF}\ln K$
$E_{cell}=E_{cell}^\circ-\frac{RT}{nF}\ln Q$	Calculate $E_{cell}$ under non-standard condition

this cell has a positive cell potential if the concentration is higher at the cathode. $Q=\frac{[Cu^{2+},anode]}{[Cu^{2-},cathode]}$

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Last update: December 15, 2021
Created: December 6, 2021