Corrosion of Metal. Ever wonder why metal corrodes? it is because of the Redox Reaction between the Metal, let's say Iron with Oxygen and Water.

Combustion of Alkanes or what we called the Organic compounds, in the presence of oxygen, meaning combustion, organic compounds are converted to carbon dioxide and water.

Exposure of Alkali Metals to Oxygen results in a formation of metal oxides.
2 5 2
when the metal is affected with water or oxygen will became rusty
That's it. Rust is a synonym of Corrosion.