SC10a Electrolysis Flashcards
Why do ionic compounds only conduct when liquid?
ions cannot move when solid but they are more free and able to move when liquid
what allows ions to move?
when an ionic solid is melted or dissolved in water, its ionic bonds break
what is an electrolyte?
an ionic substance with freely moving ions which can conduct electricity.
what is a Cation?
positive metal ion
what is a anion?
negative non metal ion
what is electrolysis?
The process in which energy transferred by a direct electrical current decomposes electrolytes.
what is a electrode?
a rod made of a metal or graphite that carries the current into or out of the electrolyte.
what is a electrode?
a rod made of a metal or graphite that carries the current into or out of the electrolyte.
which ions will move to which electrode?
positive ions (Cations) will move to the negative electrode (Cathode)
negative ions (Anions) will move to the positive electrode (Anode)
what are the two electrodes connected to?
a direct current
core practical electrolysis.
~Set up the circuit
~Turn on the power
~Wait for a few minutes
~Record your observations at the anode and cathode
~Test the gas produced by holding damp blue litmus paper near to the electrode.
~Record your observations
what happens at the anode?
negative ions lose electrons, oxidation
what happens at the cathode?
electrons are transferred from the electrode to the positive ions, reduction
what changes ions into atoms?
transfer of electrons at the electrodes changes charged ions into atoms or molecules.
write a half equation for zinc chloride?
at cathode
Zn2+ ions gain electrons and become zinc atoms:
Zn2+ + 2e- → Zn
ReduCtion takes place at the Cathode
at anode
Chloride ions lose electrons and become chlorine molecules:
2Cl- → Cl2 + 2e-
OxidAtion takes place at the Anode
