He rejected the classical elements. He defined an element as a substance that cannot be chemically broken down into simpler substances. He published "The sceptical chymist"
Discovery of Gases
JosephPriestley and CarlWilhemScheele independently discovered oxygen. Identified air as a mixture not a single element
Antonine Lavoisier
The father of modern chemistry. Introduce the law of conservation of mass. Published the first modern list of elements. Disproved phlogiston theory and emphasized combustion as a chemical reaction with oxygen
