Electrolysis Flashcards
Electrolytes
Substances that conduct electricity when aqueous or molten
When a solid is melted or dissolved in water
Ionic bonds are broken allowing free flow of ions
Cathode
Negative
Attracts cations
Anode
Positive
Attracts anions
Reduction (electrolysis)
Positive ions gaining electrons
Oxidation (electrolysis)
Electrons lost by negative ion
Uses if sodium
Street lamps
Nuclear reactor coolant
Producing hydrogen for fuel
Electrolyse water - hydrogen at cathode
What happens to ions when a molten salt is electrolysed
They are discharged as atoms/molecules at electrodes
Ions in salt water
Na+ Cl- H+ OH-
What happens when salt water is ionised and why
H atoms easiest to discharge ,go to cathode
Chloride ions discharge easier at anode
Na and OH remain and form NaOH
Products of electrolysis of slat water
H2 Cl2 NaOH
Smelting
Heating an ore with carbon
After smelting an ore
Mixture of metal and other elements remains
Purified/refined by electrolysis
Electrolysis of copper
Impure used as anode ,pure used as cathode
Anode Lose 2 electrons each and become copper ions
They dissolve in solution and migrate to cathode forming pure copper
Impurities insoluble ->sludge(may contain silver/gold/platinum)
Electroplating metal, what is plated
Cathode, and anode is pure metal
Electroplating metals what happens
Electrodes placed in electrolyte of plating metal
At cathode ,positive metal ions reduced depositing an even layer of metal atoms
Why electroplate
Aesthetics ,prevent corrosion
