When the temperature of a gas within a rigid container decreases, the particles on average move more slowly and do not collide with one another or the container walls as often. It is the the ideal gas law that applies in this situation and states that a decrease in the temperature of a gas also results in a decrease in the pressure. Thus, automobile tyres which have a colder gas in the winter sometimes need additional air to provide suffiicient pressure.
Oxidation
iron+oxygen happened
