Fractional Distillation of air

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  1. Instinct01's Avatar
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    Fractional Distillation of air
    Hey,

    I have a couple of quick questions with regards fractional distillation of air, if you wouldn't mind answering.

    1) After the air is cooled to -200C to liquefy it, carbon dioxide and water are removed. But from some sources I've read "water vapour condenses and is removed" but also "water and carbon dioxide are solids at this temperature and so are removed". So, if the water condenses, surely it's liquid before it's removed?

    2) Why is the nitrogen in gaseous form when it is distilled but the oxygen and argon in liquid form?

    Thank you
  2. charco's Avatar
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    Re: Fractional Distillation of air
    (Original post by Instinct01)
    Hey,

    I have a couple of quick questions with regards fractional distillation of air, if you wouldn't mind answering.

    1) After the air is cooled to -200C to liquefy it, carbon dioxide and water are removed. But from some sources I've read "water vapour condenses and is removed" but also "water and carbon dioxide are solids at this temperature and so are removed". So, if the water condenses, surely it's liquid before it's removed?

    2) Why is the nitrogen in gaseous form when it is distilled but the oxygen and argon in liquid form?

    Thank you
    1. In this sense, condensation means solid. The reverse of sublimation for example is condensation.

    2. All of the gases are liquids and then allowed to warm up until each one in turn becomes a gas.
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