Electrolysis Flashcards
what is electrolysis?
Electrolysis is the splitting up of electricity
how does electrolysis work?
- If you pass an electric current through an ionic substance that’s molten or in solution it breaks down into the elements its made of
- It requires a liquid to conduct the electricity, called the electrolyte
- Electrolytes contain free ions - they’re usually the molten or dissolved ionic substances
- In either the free electrons conduct the electricity
- For an electrical circuit to be complete, there’s got to be a flow of electrons. Electrons are taken away from ions at the positive electrode and given to other ions at the negative electrode. As ions gain or lose electrons they become atoms or molecules and are released
what is reduction?
Reduction is always in electrolysis and is the gaining of electrons
what is oxidation?
Oxidation is always in electrolysis and is the loss of electrons
how does reactivity affect the products formed by electrolysis?
At the negative electrode, if metal ions and H+ ions are present the metal ions will stay in solution if the metal is more reactive than hydrogen, this is because the more reactive an element the keener it is to stay as ions. At the positive electrode, if OH- and halide ions are present then molecules of chlorine, bromine or iodine will be formed. If no halide is present then oxygen will be formed
how does electroplating work?
Electroplating uses electrolysis to coat the surface of one metal with another metal. The negative electrode is the metal object you want to plate and the positive electrode is the you want it to be plated with. The electrolyte must also contain the ions of the plating metal