preserving metals

ferrous

presence of iron in metals such as steel. making metals more prone to react with oxygen 

non ferrous 

metals that don’t contain iron molecules such as copper and zinc, they more expensive 

rust

caused by corrosion of iron + iron alloy through oxidation

oxidation

reaction of metal with o2

problem with painting

any small area where paint chipped is exposed to air so rust will form

galvanizing

zinc used as its resistant to corrosion

electroplating

coating of zinc by electrolysis