First “chemist” to perform truly quantitative experiments, measuring the pressure of air and its relationship to its volume.
Invented the term phlogiston, which was thought to flow from burning materials
Determined that oxygen fueled the combustion of materials and was originally called “dephlogisticated air”
Worked with exact measurements of gases, and explained the true nature of combustion. Verified the Law of conservation of mass. Named oxygen.
Determined that a given compound always contained exactly the same proportions of elements by mass. First known as Proust’s Law but later called law of definite proportions.
Determined the law of multiple proportions, by comparing the mass amounts of an element in different compounds with the same element. e.i. CO CO2.
Theory that stated that: 1) each element is made up of tiny particles called atoms 2) Atoms of a given element are identitical, different elements are fundamentally different
3) Compunds are formed when atoms of diff. elements combine, a given compound always has the same relative numbers and types of atoms. 4) Chemical reactions involve reorganization of atoms, changes way they bond not atoms themselves.
Helped determine the key to absolute formulas by combining specific volumes of two gases like hydrogen and oxygen or hydrogen and chlorine. Found that 2 volumes of hydrogen + 1 volume of oxygen yielded to volumes of gaseous water.
Created the hypothesis that suggested that equal volumes of differnt gases contain that same number of particles. This hypothesis assumed that the distances between the particles in a gas were very great compared to that of their size