Topic 4 Electrolysis Flashcards
What is electrolysis
The splitting of ionic compounds using electricity
What is an electrolyte
A molten ir dissolve ionic compound
Can conduct electricity
Where do the positive ions (cations) move to
The negative negative electrode ( cathode)
What happens at the negative electrode (cathode)
Gain electrons (reduced)
What material goes to the cathode
Metal
Where will the negative ions (anions) go to
The positive electrode (anode)
What happens at the anode
Lose electrons (oxidised)
What material goes to the anode
Oxygen or nonmetal from the electrolyte
What creates a flow of charge
As ions travel to the electrodes
Why can’t ionic solids be electrolysed
Because they are in fixed positions and can’t move
Why can ionic compounds be electrolysed
Because the ions move freely and conduct electricity
Reaction of Pb at cathode
Pb2 + 2E- -> Pb
Reactions of Br at anode
2BR-> Br2 + 2E-
When is electrolysis used to extract metals from ores
If the metal is to reactive to be reduced by carbon or reacts with carbon
Why is extracting metals from ores using electrolysis expensive
Lots of energy is required to melt the ore and produce the required current
