Electrolysis/Rechargeable Flashcards
1
Q
Define electrolytic cell
A
- a electrolytic cell turns electrical energy into chemical energy by driving a non-spontanous reaction
2
Q
Predicting electrolytic reactions
A
- circle everything on the electrochemical series
- look for smallest positive gradient
3
Q
electroplating cells
A
- When a material is covered in a thin layer of metal to improve appearance or give properties to the outside
- The object being plated is always the cathode
4
Q
Common design features
A
Continous removal of products:
- some products that form can spontaneously react
Inert electrodes
- electrodes that react need to be replaced
Electrolyte
- Choosing between molten or aqueous electrolytes allows optimization for the reaction’s efficiency.
Chemical additives to electrolyte
- Adding chemicals to lower the melting point of a molten electrolyte reduces the energy needed for the reaction
5
Q
Faradays laws
A
Q = It
Q = n(e) x F
6
Q
Rechargeable Cells
A
- Rechargeable cells are secondary cells whereas regular cells are known as primary cells.
- Solid must be produced at both electrodes in order to be rechargeable
- Place of reduction and oxidation doesn’t change but the polarity of the electrode does
7
Q
Green hydrogen
A
- Electrolysis of water
- PEM electrolyser
- Artificial photosynthesis
1. which must be given energy through zero carbon emmisions
8
Q
Electrolysis of water
A
- A simple process used to obtain green hydrogen using electrolysis of dilute sulphuric acid solution
- Hydrogen gas is produced and oxygen gas
9
Q
PEM electrolyser
A
- Product of hydrogen is compressed
- solid proton exchange membrane
10
Q
Artificial photosynthesis
A
- Sunlight hits the anode and causes metals excite
- Energy causes them to oxidise water to oxygen gas and hydrogen ions
- Hydrogen ions migrate to cathode
- Reduction of hydrogen ions to hydrogen gas occurs
- Considered as photosynthesis as instead of glucose produced hydrogen is produced
