Ask A Scientist Chemistry Archive

name         Lucy P.
status       student
age          12

Question -   What is the name of the process that is used to
extract the gases from the air?
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Hi, Lucy !!!

The LINDE process was one of the successful attempts
at super-refrigeration. Devised in 1896 by Karl Linde, the
process allowed him to cool gasses at very low temperature, thus 
liquefying them.

The process had a compressor to pump the air to a high
pressure, let the pressure fall as it traveled through a tube,
and then used that cooled air to reduce the temperature of
the incoming air by having it travel back to the first tube
through a second tube inclosing the first.

So, alternatively, compressed, cooled, expanded,
the expansion resulting each time in a considerable
reduction of temperature, the gases than move at a lower
speed, occupy less space and so the air  changes phase
to become a liquid.

Alcir Grohmann
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