Electrolysis Flashcards
What is electrolysis
Passing an electric current through an ionic substance that’s molten or in solution to break it down into new substances
What is an electrolyte
A liquid that conducts electricity
How to test for an electrolyte
Put a conductivity probe in the solution. If electricity is present - it is an elctrolyte
Why do ionic substance conduct electricity when molten or in solution
Because the ions are free to move
Why don’t covalent substances conduct electricity
Because they have no free ions
What ions are there in electrolysis of aqueous solutions
There will be hydrogen and hydroxide ions from the water
In aqueous solutions what happens to the hydrogen ions ions and what happens to the hydroxide ions
The H+ ions go to the -ve cathode
The OH- ions go to the +ve anode
At the cathode, what happens if the metal ions are less reactive than the H+ ions
A solid layer of the pure metal will be produced instead
At the cathode, what happens if the metal ions are less reactive than the H+ ions
Hydrogen gas will be produced
At the anode, what happens if halide ions are present
Molecules of chlorine, bromine or iodine will be formed
At the anode, what happens if no halide ions are present
Oxygen will be formed
How can you increase the number of electrons transferred in electrolysis
Electrolysing for a long time
Increasing the current
What does one faraday represent
One mole of electrons
