Jacques Charles (1746-1823)

Charles was a French chemist who was also a teacher and a minor government official.
Charles is best known for stating the law that every gas expands by the same amount for a rise in temperature of one degree.
This means that the volume of a fixed amount of gas is directly proportional to the temperature if the pressure remains constant.
Charles did not publish his research and it was later duplicated by Gay-Lussac.
He was also interested in ballooning and suggested balloons could be filled with the very light hydrogen gas.


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