Why do aluminium sheets not corrode easily?
Answers
When it comes to aluminium it does not corrode so easily under moist conditions when compared to steel or iron.
One of the main reasons being that the aluminium sheet is covered in a layer of aluminium oxide which protects it from the moist conditions.
This layer of aluminium oxide prevents the aluminium from coming into contact with oxygen or air.
Aluminium when reacts with air forms aluminium oxide which protects the underlying metal from further oxidation . This is not porous and flaky like rust and it can acts like a film or protective cover which protects the metal. So aluminium do not rusts.
Coper turns green due to formation of copper carbonate which is formed by reaction of copper with carbonic acid and air. Acid rain has carbonic acid, so it can easily turn copper green
Hope it helps.....