Chapter 23 - Redox + electrode potentials Flashcards
1
Q
Define standard electrode potential
A
The EMF of a half cell compared with a standard hydrogen half cell. This is measured under standard conditions (1 mol dm-3, 298K and 1 atm)
2
Q
How to work out the overall cell potential?
A
EMF(cell) = E(+ve) - E(-ve)
3
Q
Why is a salt bridge needed?
A
Completes the circuit/full loop
4
Q
Why are platinum electrodes used?
A
They are metallic, so will conduct electricity
They are inert, so will not interfere with the reaction
5
Q
What is the standard EMF of an electrode directly proportional to?
A
- ln(K), K=equilibrium constant
- Total entropy change
6
Q
What are the limitations of using electrode potentials to determine feasibility?
A
It tells you if the reaction is feasible or not but does not consider kinetics, rate and concentration, or that conditions may deviate from standard conditions
