Electrode Potentials Flashcards
What is a half cell?
Contains the chemical species present in a redox half equation
Describe the components that make up a metal/metal ions half cell.
Solid metal rod dipped into a solution of its aqueous ions
What does the direction of electron flow between two half cells depend on?
The relative charge of each half cells
-ve to +ve
What components make up an ion/ion half cell?
A platinum rod dipped into a solution of the mixture of aqueous ions
Which electrode is the negative electrode?
The more negative electrode potential as it is oxidised so has a tendency to lose more electrons
Which electrode is the positive electrode?
The more positive electrode as it has the tendency to gain electrons and be reduced
What is the standard electrode potential?
The tendency to gain electrons and be reduced
What are the standard condition used in standard electrode potentials?
- 1 moldm-3 solutions
- 298K
- 100kPa
How are two half cells connected?
- voltmeter connected to the two rods
- salt ridge between the two solution for the movement of ions
How are cell potentials calculated?
Cell potential of (positive electrode - negative electrode)
Where is the strongest oxidising agent and the strongest reducing agent found on a redox system table?
Strongest OA = bottom left
Strongest RA = top right
What are the limitations of making predictions using electrode potential values only?
- no indication of reaction rate
- if concentration is not 1moldm-3
- not all reactions take place in aqueous conditions
