C3.3 Electrolytic Processes Flashcards
What are the names of the two electrodes?
The positive electrode is the anode and the negative one is the cathode.
What are the names of charged particles?
Positive is Cation
Negative is Anion
What is an electrolyte?
An ionic substance that is molten or dissolved in water.
What conducts the electricity in an electrolyte?
The free ions.
What is oxidation and reduction?
Oxidation is a loss of electrons
Reduction is a gain of electrons.
What are half equations?
Equations that show what happens to ions at the cathode or anode.
What are the products for electrolysis of Sodium chloride?
Sodium and chlorine.
Which ion is discharged at the anode for electrolysis of a dissolved electrolyte?
The simplest one.
What is discharged at the cathode?
Either a metal that is less reactive than hydrogen or hydrogen.
What are the products of the electrolysis of copper chloride?
Cathode: copper
Anode: Chlorine
What are the products of the electrolysis of Copper sulphate?
Cathode: copper
Anode: oxygen
What are the products of the electrolysis of Sodium sulphate?
Cathode: hydrogen
Anode: oxygen
In order to purify copper, which electrode is pure and which is impure?
The anode is impure and the cathode pure.
During copper purification by electrolysis, what happens at the anode?
Copper particles dissolve into the solution. The anode decreases in mass.
During copper purification by electrolysis, what happens at the cathode?
The copper ions in the solution are discharged at the cathode. It increases in mass.
What mass changes occur during the electrolysis of copper sulphate using copper electrodes?
The cathode gains mass whilst the anode loses mass.
What is electroplating?
Applying a thin layer of metal to another metal.
What are the purposes of electroplating with gold or silver?
To make it look nicer
To add value
To make it unreactive.
What is the purpose of electroplating with non valuable metals?
To protect the metal from corrosion
To make the metal weather resistant
To make it unreactive.
What is the cathode, anode and electrolyte during electroplating?
The cathode will be the object that needs to be electroplated
The anode is a bar of the metal used for electroplating.
The electrolyte contains atoms of the metal you want to electroplate with.
What household item is electroplated?
Iron cutlery is electroplated with nickel or chromium.
In terms of electrons, what happens at the electrodes?
At the cathode, electrons are transferred to the positive ions
At the anode, electrons negative ions lose electrons
