(c. 980 – 1037)
Persian polymath; the foremost physician and
philosopher of his time. He was also an astronomer,
chemist, geologist, logician, paleontologist, mathematician,
physicist, poet, psychologist, soldier, statesman, and teacher.
He invented the refrigeration coil, which
condenses aromatic vapors.
This was a breakthrough in distillation
technology and he made use of it in his
steam distillation process to separate
temperature sensitive material and
produce essential oils.
Development of the Kelvin Absolute
• William Thomson (later Lord Kelvin) was
interested in Charles’s Law which states that
when a gas is cooled by one degree Celsius,
it’s volume drops by 1/273
– This would lead to zero volume at -273
– How can matter exist without taking up
• Thomson instead suggested that it was the
energy of motion that decreased with
– At -273
C, the molecules cease motion
and essentially not take up space
– He called -273
C absolute zero because
no further temperature reduction is
This later became known as 0
University of Glasgow
World of Scientific Discovery
Liquefaction of Oxygen
Liquid oxygen is the liquid form of element oxygen. In nowadays it is widely used
in many fields.
Liquefaction of substance that normally exists as gas dates back to the 18th century.
The first successful attempt was made by a French mathematician Gaspard Monge,
who liquefied sulfur dioxide in 1784. In the following decades, people succeeded
in liquefy many gases, but none of them was able to liquefy oxygen gas. In the
late 1840s, Irish physical chemist Thomas Andrews suggested that every gas has a
precise temperature, which is the critical temperature. Above the temperature gas
cannot be liquefied even under great pressure. Following Andrews idea, scientist
came up with the idea of using ’cascade’ process to get low temperature. In this
method, one liquefied gas is used to cool another gas with lower critical temperature,
and so on. By using the cascade process, French physicist Louis Paul Cailletet
liquefied three gases, oxygen, nitrogen and carbon monoxide.
Now liquid oxygen is playing a significant role in both industry and research.
Compare with oxygen gas, liquid oxygen is much easier to store and transport.
Liquid oxygen is stored in hospitals for patients with breathing problems. It is
also used as oxidizer in industry, such as producing ion and many other metals.
Furthermore, liquid oxygen is used as oxidizer in spacecraft such as rockets. Without
liquefaction of oxygen, one cannot provide enough oxygen with such limited
space and cannot put rocket into use.
Liquefaction of oxygen is an important event in the history. It was one of the human