Question

the process of depositing a uniform layer of aluminium oxide on aluminium by electrolysis is called

Answer 1

 pure aluminum is attracted to the cathode, which is a lining of graphite. The oxygen is attracted to the anode, and bubbles through the solution.

At the cathode, reduction takes place as electrons are gained:

Al3+ + 3e- ® Al

At the anode, oxidation takes place as electrons are lost:

2O2- ® O2 + 4e-

At the anode also, the oxygen formed will react with the anode (which is made of carbon) to form carbon dioxide. This means the anodes must be frequently replaced.

This process uses A lot of electricity and is expensive. Therefore, aluminum is much more expensive than other metals that are easier to extract (like iron, but its desirable characteristics mean that it is still widely used.

Uses

Aluminum is the most widely used metal after iron. It is mostly used in an alloy with another metal, this means it is mixed with another metal to produce another compound that has a certain desirable characteristic - like stainless steel.

Answer 2

Is it anodising...
Hope it helped you...