Chapter 6B - Electrolytic Cell Design Features Flashcards
(12 cards)
1
Q
What is an electrolyte?
A
Contains free moving ions that can either donate or accept electrons
2
Q
Define Electrodes
A
- site of electrolysis
- must be conductive
3
Q
Define Battery
A
- defines polarity of electrodes
- provides external source of electrons
4
Q
What does conductive mean?
A
Allows electrons to move in the external circuit.
5
Q
What are the similarities between an electrolytic cell and a galvanic cell?
A
- oxidation occurs at the anode
- reduction occurs at the cathode
- electrons flow through an external wire
6
Q
What are the differences between an electrolytic cell and galvanic cell
A
- converts electrical energy to chemical energy
- anode is positively charged
- cathode is negatively charged
- Non-spontaneous reaction
- Does not require seperate half cells
- Power supply is required
7
Q
Describe the anode in an electrolytic cell
A
- positively charged
- connected to the +ve terminal of power source
- attracts anions in the electrolyte
8
Q
Describe the cathode in an electrolytic cell
A
- negatively charged
- connected to the negative terminal of the power supply
- attracts cations in the electrolyte
9
Q
Describe Molten Electrolytes
A
- require high temperatures
- can be hazardous and expensive
10
Q
Define Additives
A
- unreactive
- added to molten electrolytes to reduce the melting point
- make electrolyte safer and cheaper
Note: can be the product of some reactions and may spontaneously react
11
Q
Why must we consider the nature of the electrodes?
A
- an inert electrode will not take part in the reaction
- a metal electrode can undergo oxidation at the anode if it is the strongest reductant present.
12
Q
What is the minimum voltage of an electrolytic reaction?
A
- potential difference is greater than the spontaneous reverse reaction
- energy is lost in cell, typically as heat
