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Questions
Give reasons.
Aluminium is a highly reactive metal, yet it is used to make utensils for cooking.
Explain why aluminium is a highly reactive metal. Still, it is used to make utensils for cooking.
Solution
- Aluminium is a highly reactive metal. It reacts easily with oxygen in the air and forms a layer of aluminium oxide on its surface.
- This aluminium oxide layer is very tough and does not allow air to enter the metal for further reaction, preventing further corrosion of aluminium.
- Therefore, aluminium articles become unreactive towards air and water and do not corrode easily due to the presence of a strong aluminium oxide layer over them.
- This oxide layer on aluminium is made further stronger by making it thicker through a process called anodising. This prevents corrosion to the maximum. Hence, aluminium becomes highly resistant to corrosion and is used to make cooking utensils.
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