What is the main purpose of anodising aluminium during its surface treatment process?
To form thicker oxide layer preventing corrosion
Aluminium naturally forms a thin layer of aluminium oxide on its surface when exposed to air, and this layer protects the metal underneath from further reaction.
In anodising, aluminium is made the anode in electrolysis with dilute sulphuric acid. The oxygen released at the anode reacts with the aluminium and builds up a much thicker oxide layer, which makes the metal more resistant to corrosion and can also be dyed for an attractive finish.
Anodising does not improve conductivity (the oxide layer is actually a poor conductor), it does not mix aluminium with other metals to make an alloy, and it builds up the oxide layer rather than removing it.
Hence, To form thicker oxide layer preventing corrosion.
Similar Questions
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c. An alloy is a heterogenous mixture of two or more metals.
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Important Questions from Metals & Non-metals
Due to improper/indiscriminate disposal of hold and used computers or their parts, which of the following are released into the environment as e-waste?
1. Beryllium
2. Cadmium
3. Chromium
4. Heptachlor
5. Mercury
6. Lead
7. Plutonium
Select the correct answer using the codes given below:
Recently, there has been a concern over the short supply of a group of elements called 'rare earth metals'. Why?
1. China, which is the largest producer of these elements, has imposed some restrictions on their export.
2. Other than China, Australia, Canada and Chile, these elements are not found in any country.
3. Rare earth metals are essential for the manufacture of various kinds of electronic items and there is a growing demand for these elements.
Which of the statements given above is/are correct?
Which of the following metals CANNOT be cut with a knife?
Which of the following will be formed when dilute hydrochloric acid is added to a beaker having copper oxide ?
Which of the following statement is incorrect regarding metals?
