C6 - Electrolysis Flashcards
(20 cards)
Why is gold found in the Earth’s crust as the metal itself?
It is unreactive
What is an ore?
A material containing enough metal in it for it to be economically worthwhile to extract the metal
What process is used to extract a metal less reactive than carbon from its ore?
Reduction with carbon
What process is used to extract a metal more reactive than carbon from its ore?
Electrolysis
What is electrolysis?
Using electricity to produce elements from an ionic compound
What is an electrolyte?
A liquid or aqueous ionic compound
What is the name for the positive electrode?
The anode
What is the name for the negative electrode?
The cathode
Do positive ions move to the anode or the cathode?
Cathode
Do negative ions move to the anode or the cathode?
Anode
What are the two main disadvantages of using electrolysis to extract metals?
Requires a large amount of energy to melt the compounds and to produce electricity
Why is aluminium oxide mixed with cryolite when extracting aluminium?
To lower the melting point
What is produced at the anode and cathode in the electrolysis of aluminium oxide?
Aluminium at the cathode and oxygen at the anode
Why does the anode need to be replaced in the electrolysis of aluminium oxide?
The oxygen reacts with the carbon electrode to produce carbon dioxide - burns away the anode
For a simple ionic liquid where is the metal produced?
Cathode
For a simple ionic liquid where is the non-metal produced?
Anode
In the electrolysis of an ionic solution when will hydrogen be produced?
If the metal is more reactive than hydrogen
In the electrolysis of an ionic solution when will oxygen be produced?
If the non-metal is not a halogen
What can happen to the water molecules in the electrolysis of solutions?
They break down into hydrogen (H+) and hydroxide (OH-) ions
What is a half equation?
An equation which shows electron transfer at one of the electrodes.
