CHEM 115 Lecture Notes - Lecture 6: Gravitational Energy, Electric Potential Energy, Phlogiston Theory
Document Summary
Antoine lavoisier"s careful measurements of combustion reactions finally disproved the old phlogiston theory. A sample of tin heated in a closed container formed a white rust and the total weight of the container remained the same. When the container was opened, air rushed in and upon weighing the container again the weight it gained was exactly equal to the weight gained by the tin. The conclusion was that the tin must have combined with some of the air. Lavoisier"s recognition of the significance of cavendish"s experiment was the nail in the coffin of the phlogiston theory. His reasoning was that priestley"s dephlogisticated air was really a new element that he named oxygen and cavendish"s pure phlogiston was a new substance which he called hydrogen meaning "water generator". Lavoisier proposed a new theory in which the heat of combustion reactions is a subtle fluid that he called caloric as the substance of heat.
