rust (chemistry)

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Reddish-brown oxide of iron formed by the action of moisture and oxygen on the metal. It consists mainly of hydrated iron(III) oxide (Fe₂O₃.H₂O) and iron(III) hydroxide (Fe(OH)₃). Rusting is the commonest form of corrosion.

Rust prevention
There are two main approaches to protect against rusting. Barrier methods introduce a barrier between the metal and the air and moisture to minimize the reaction. This is the commonest method of rust prevention and the barrier may consist of a layer of grease, paint, plastic, or an unreactive metal, such as tin, copper, or chromium.

In sacrificial protection, the iron is actually covered by a more reactive metal, such a zinc (galvanization), or connected to a more reactive metal, such as magnesium, so that as long as the ‘sacrificial’ metal is present it will corrode first.

The three stars are taken from the arms of the Duchy of Selje. The flag uses the pan-Slav colours. Effective date: 25 June 1991. >>