standard electrode

what are the standard conditions ?

100 kPa

298K

1.00 mol dm-3

in electrode potential - half equation always written in reduction form

Mg 2+ + 2e- → Mg

standard electrode potential

electrode potentials measured under standard conditions, donated by symbol E0.

Non - standard electrode potential

are used by Le Chatelier’s principle - if equilibrium change, the equation will oppose change back to equilibrium.

temperature - if higher than 298 K

then the system will move in the endothermic direction and the electrode potential will change accordingly.

pressure - if greater than 1atm

then system will move to decrease the pressure and the electrodes potential will change accordingly.

concentration - if greater than 1.0 mol dm-3

will favour reduction and the electrode potential will be more positive than the standard electrode potential.

concentration - if lower than 1.0 mol dm-3

will favour oxidation, the electrode potential will be more negative than the standard electrode potential.

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a change which favour reduction direction will make the electrode potential more positive,

a change which favour oxidation direction will make the electrode potential more negative.