Question

Is the process of rusting, precipitation or corrosion and why?

Answer 1

rusting is corrosion caused by the oxidation of iron. Rust is the product and iron is the reactant. Left alone for long enough all the iron in a given situation would be used up and all that would remain is rust.

As oxygen (from h2o or other aqueous electrolyte) combines with exposed iron, iron bonds with oxygen to form iron oxide and releases electrons. This process is corrosion.

The overall process is corrosion, but there is precipitation in parts of the mechanism. Iron Oxide generally precipitates out of iron hydroxide