Electrolysis (P1C13)

Question 1

What is electrolysis?

Answer 1

Electrolysis is the use of an electrical current to break down compounds containing ions into their elements.

Question 2

Which electrode is negative?

Answer 2

The negative electrode is the cathode.

Question 3

What can be used to lower the melting point of aluminium?

Answer 3

The melting point of aluminium can be lowered by adding cryolite to the solution.

Question 4

Why does the positive electrode have to be replaced frequently when used to extract metals from their oxides?

Answer 4

Because the oxygen from the metal oxide reacts with the carbon of the electrode to form carbon dioxide, which bubbles to the surface.

Question 5

What is produced at the negative electrode during the electrolysis of an aqueous solution?

Answer 5

During the electrolysis of an aqueous solution, hydrogen is produced if the metal is more reactive than hydrogen. Otherwise, the metal is produced.

Question 6

What is produced at the positive electrode during the electrolysis of an aqueous solution?

Answer 6

During the electrolysis of an aqueous solution, a halogen is produced if present. Otherwise, oxygen is produced.