Kitchen articles like pressure cooker, pan etc. are anodized.

1. Anodising is a technique used to make aluminium surface resistant to corrosion and abrasion.

2. In this process, the anode reaction results in formation of black coloured thin film of aluminium oxide on the surface of article.

4Al + 3O₂ ® 2Al₂O₃

3. Kitchen articles like pressure cooker, pan etc are constantly subjected to heat, pressure and water causing corrosion and abrasion.

4. To avoid this, kitchen articles are anodized.