SC10 Electrolytic Processes Flashcards
Define cathode
A negative electrode
Define anode
A positive electrode
Define electrode
A rod of metal or graphite through which an electrical current flows in or out of an electrolyte
Define electrolyte
Ionic compound in molten or dissolved solution that conducts the electricity
Define electrolysis
The process in which energy, from a direct current supply, decomposes electrolytes
What ions go towards the cathode?
Cations
What ions go towards the anode?
Anions
What direction do electrons move during electrolysis?
From the power supply to the cathode
What occurs at the anode?
Negative ions lose their electrons
What occurs at the cathode?
Electrons are transferred to the positive ions
What ions will be present in the electrolysis of an aqueous solution?
- The ions of the electrolytes
- OH- ions
- H+ ions
Why are OH- and H+ ions present in aqueous solutions?
Since aqueous substances are those dissolved in water, water will always be present. Those are the ions present in water
What is produced at the cathode of the electrolysis of an aqueous solution?
Hydrogen (from H+ in water) is produced UNLESS the + ions in the ionic compound are from a metal that is less reactive than hydrogen. If the metal is less reactive, it will be produced instead
What are the metals that are less reactive than hydrogen?
- copper
- silver
- gold
- platinum
What is produced at the anode of the electrolysis of an aqueous solution?
Oxygen (from the OH-) and water UNLESS there is a group 7 ion present. If so, then it will be produced