Electrolysis Flashcards
What is Electrolysis used to make
New substances
What is Electrolysis
When you pass an electric current through an ionic substance which is molten or in solution which breaks into new substances
What is an electrolyte
The liquid that conducts electricity
What happens at the anode
Electrons are taken away from the ions
What happens at the cathode
Electrons are given to the ions
Which is the positive electrode
Anode
Which is the negative electrode
Cathode
What happens at the cathode when it is in aqueous solution
Hydrogen gas will be produced if the metal ions a more reactive than Hydrogen ions
If the metal is less reactive the hydrogen then the metal will be produced
What happened to the anode in aqueous solution
If halide ions are present the halogen is formed
If no halide ions are present then oxygen and water will form
What does the amount of product made depend on
The number of electrons that are transferred
How do you increase the amount of substance produced
- Electrolysing for a longer time
- Increasing the current
Relationship between Charge, current and time
Charge= current x time
What does one Faraday equal
96,000 coulombs
What does one faraday contain
One mole of electrons
How do you find the mass produced during electrolysis
1) write out the balance half equation
2) Calculate the number faradays
3) divide the number of faradays by the number of electrons in the half equation
= moles
4) use mass = moles x Mr
