Unit 2 - Electrolysis Flashcards
What is electrolysis
When you pass an electric current through an ionic substance that’s molten/in solution and it breaks down into the elements it’s made of
What is the electrolyte
The liquid required to conduct the electricity
What sort of ions do electrolytes contain?
Free ions
For an electrical circuit to be complete, what does there have to be?
A flow of electrons
Why do metals conduct electricity?
Because they have delocalised electrons which are free to carru charge through the solid structure
What happens in electrolysis?
When the solid is melted/dissolved the ions become free and move so that they can carry charge
What happens when the power supply is switched on?
The electrodes become positively and negatively charged
what ions are attracted to which electrodes?
Positive + ions are attracted to the negative electrode and negative - ions are attracted to the positive electrode
What happens to the ions at the negative electrode?
The positive ions gail electrons
eg Na+ + e- → Na
What happens to the ions at the positive electrode
The negative ions loose electrons
eg 2Cl- → Cl2- + 2e
What are the equations involving electrons known as?
Half equations
What is the loss of electrons known as?
Oxidation
What is the gain of electrons known as?
reduction
what does OILRIG stand for?
Oxidation
Is
Loss
Reduction
Is
Gain
What substances form at the negative electrode?
Metals or hydrogen
