Which French chemist proved that combustion requires oxygen?

Antoine Lavoisier proved that combustion requires oxygen. In the 1770s, he used carefully measured experiments to show that burning substances combine with a component of air, which he identified as oxygen.

Lavoisier challenged the older phlogiston theory, which claimed that combustible materials released an invisible substance during burning. His experiments with mercury, lead, sulfur, and phosphorus showed instead that combustion involves gaining oxygen and usually forming an oxide.

The discovery helped establish the modern concept of chemical elements and conservation of mass. Lavoisier also helped introduce a systematic chemical naming system and supported the use of precise balances in laboratory work.

Joseph Priestley and Carl Wilhelm Scheele independently isolated oxygen, but neither correctly explained its role in combustion. Priestley called it “dephlogisticated air,” while Lavoisier interpreted the evidence within a new oxygen-based theory.