prevention of rusting

Rusting can be prevented, by applying a protective coating on the surface of the iron, so that the iron does not come in contact with air and moisture simultaneously. This coating can be of two types: (i) Non-metallic coating (ii) Metallic coatin..

Rusting of Iron - Who has not seen the damaging effects of rusting of iron! During the process of rusting the oxide that forms is brittle and chips off from the surface. This exposes yet another layer below to the deleterious effects of moisture and air. Thus, rus..

Conditions for Rusting of Iron - The presence of water and oxygen is essential for the rusting of iron. Impurities in the iron, the presence of water vapor, acids, salts and carbon dioxide hastens rusting. Pure iron does not rust in dry and carbon dioxide fre..

>This 'rusting' can be prevented by connecting iron to a more reactive metal (e.g., zinc or magnesium). This is referred to as sacrificial protection or sacrificial corrosion, because the more reactive protecting metal is preferentially oxidised away, leaving the protected metal..

Non-metallic coatings include painting, varnishing tarring, plastic coating, oiling, greasing, enamelling etc. As matter of fact, every housewife knows that applying a thin layer of oil on the surface of iron utensils and implements will prevent their rusting..

Eelectroplating with metals like nickel, chromium, cadmium etc. prevents rusting. Galvanising and tinning are also very effective metallic coatings. Galvanising involves dipping of iron sheet into molten zinc. A thin layer of zinc sticks to the iron. In tinning, tin is used ins..

The nails do not rust. They have water, but no oxygen. Boiled water does not contain any dissolved oxygen. The thin layer of oil prevents oxygen in air from reaching the water in the test tub..

. Anthracene can also be used in insecticides and for a wood preservative. This compound is widely abundant. It is found in any type of coal or tar. Like anthracene, phenanthrene is used in the production of dyes. It is also used in the manufacture of explosives, and is an important starting materi..

. The major problem of corrosion occurs with iron (or steel) as it is used as a structural material in industries like construction, infrastructure, bridges, rail transport power transmission, shipbuilding, automobiles, heavy industries etc. Aluminium, another useful structural metal, also undergoe..