How can pure oxygen be obtained from air?
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This is not a reaction I would be happy doing, and is the preserve of the specialist. Industrially, they compress, and liquefy air, and then perform a fractional distillation. The normal boiling point of dinitrogen is
Liquid oxygen is likewise very cold, but an oxidant par excellence, and something that would have to be very carefully handled. If you have ever seen a magic show, you might see some spectacular demonstrations of combustion using liquid oxygen.