Science

discovered hydrogen by dissolving metals in acids

identified hyrdogen

discovered that hydrogen gas was lighter than air (not yet identified)

showed that bombarding nitrogen atoms with alpha particles created oxygen (1919)

motivated to research gas through hot air balloons, created hydrogen-powered balloon with the Robert brothers

invented the Law of Partial Pressures

called oxygen "fire-air" after first producing it

heated HgO which led to his discovery of oxygen

developed equation used to monitor behavior of non-idea gases

observed that "fixed air" (CO2 gas from heated CaCO3) was heavier than air, could be poured like a liquid, extinguished flames, killed animals (was trying to find a cure for kidneystones); latent heat, heat of fusion, heat of vaporization

developed scientific explanation for combustion, refuted phlogiston theory (when materials burned, they produced undectable substance)

introduced term "gas," developed effective balance, anticipated Law of Conservation of Mass; used chemistry to try and understand causes of disease

discovered that dissected frogs would twitch because of "animal electricity"; disputed by Alessandro Volta who said electricity produced by two metals touching

created Law of Definite Proportions: elements combined in defined ratios to form compounds