Home Preparation for National Talent Search Examination (NTSE)/ Olympiad
Chapter : 1. Metals & Non Metals
Important Terms And Concepts
10. Anodising : The process of forming oxide layer on the surface of metal is called anodising, e.g., Aluminium forms an oxide layer on its surface when exposed to air. It is non-penetrating layer which protects it from corrosion. The layer can be made more thick with the help of anodising. It is a process in which cleaned aluminum metals is taken as anode. Dilute H2SO4 acts as electrolyte. When electric current is passed, O2 gas is liberated which reacts with aluminium to form a layer of aluminium oxide. The oxide layer can be made coloured like red, blue, etc., so as to make it more attractive for making decorative articles. Metal burns in presence of oxygen to from metal oxide. Let us perform and experiment.