5.4.2 Standard Electrode Potentials Flashcards
1
Q
What factors does the electrode potential depend on?
A
- Temperature
- Pressure of gases
- Concentration of reagents
2
Q
What are the standard conditions used when comparing electrodes?
A
- Concentration of 1 mol dm^-3
- Temp of 298K
- Pressure of 100 kPa
- Made using a high resistance voltmeter so no current flows, and maximum PD is achieved
3
Q
What is the standard electrode potential Eꝋ?
A
Potential different produced when a standard half cell is connected to a standard hydrogen cell under standard conditions
4
Q
What are the 3 types of half-cell that can be connected to a standard hydrogen electrode?
A
- Metal / metal ion half cell
- Non-metal / non-metal ion half cell
- Ion / ion half cell (different oxidation states)
5
Q
What occurs at the positive and negative electrodes?
A
- Reduction at positive electrode
- Oxidation at negative electrode
6
Q
What happens in non-metal / non-metal ion half cells with a standard cell?
A
- Pt is the electrode for both sides (inert, takes no part in reaction, like graphite)
7
Q
What happens in an Ion / Ion half-cell?
A
- Pt electrode used (Foil)
8
Q
How do you calculate Eꝋ ?
A
Ecellꝋ = Erightꝋ - Eleftꝋ
(more positive - less positive)
Ecellꝋ = Ereductionꝋ - Eoxidation
