An ancient Greek philosopher who adopted atomic theory from his mentor Leucippus who originally proposed it.
Aristotle contributed to modern atomic theory by introducing alchemy, an ideology that chemists eventually rebelled against.
He discovered the Law of Conservation of Mass which states that matter is neither created nor destroyed in a chemical reaction. Atoms are rearranged.
He discovered the Law of Definite Proportions.
John Dalton reintroduced atomic theory to explain chemical reactions. He also combined the work of Democritus’s definition of atoms and elements, Proust’s Law of Definite Proportions, and Lavoisier’s Law of Conservation of Mass.
British chemist and physicist known for his discovery of the element thallium, and his cathode-ray studies, crucial in the development of atomic physics.
He found that the energies radiated by hot objects have distinct values, with all other values forbidden. This discovery was the beginning of quantum theory.
He discovered radium and polonium while studying radioactivity with his wife, Marie Currie.
She is known for the discovery of the elements polonium and radium alongside her husband, Pierre Currie.
He discovered the charge-to-mass ratio of the electron.
He is the father of nuclear chemistry and physics. He discovered and named the atomic nucleus, the proton, the alpha particle, and the beta particle.
She along with fellow chemists, Hahn and Strassmann, collaborated with one another to discover uranium fission. She is an important figure in the fields of radioactivity and nuclear physics. She is also widely credited as the discoverer of protactinium.
Known for the theory of relativity which laid the basis for the release of atomic energy
He collaborated with both Lise Meitner and Fritz Strassmann. With Metner, he discovered protactinium, the long-lived mother substance of the actinium series. He also discovered uranium Z, the first case of a nuclear isomerism of radioactive kinds of atoms. He, Meitner and Fritz Strassmann, also collaborated on the processes if irradiating uranium and thorium with neutrons.
known for research on quantum theory and predicting the wave nature of electrons
He discovered radioactivity.
A french scientist who collaborated with her husband, Frederic Joliot-Curie, in researching the structure of an atom. She discovered how to synthesize designer radioactive elements.
A french scientist who collaborated with his wife, Irene Joliot Curie, with research on the structure of an atom.
He used the Cathode ray tube to describe negative particles called electrons and measured the charge to mass ratio.
-An italian physicist who created the world's first nuclear reactor
-Called the "architect of the nuclear age" and the "architect of the atomic bomb
He contributed to the atomic theory by including quantum mechanics, the branch of mechanics, based on quantum theory, used for interpretating the behavior of elementary particles and atoms.
Lawrence invented the cyclotron which is used to discover a large number of new chemical elements and new isotopes.
He was responsible for leading, collecting, and coordinating the team that developed and donated the first atomic bomb.
Proposed a theory for the hydrogen atom based on quantum theory. It has three rules:
1.) Electrons only exist in certain allowed orbits
2.) Within an orbit, the electron does not radiate
3.) Radiation is emitted or absorbed when changing orbits
known for his contributions to the quantum physics
He found the neutron which has no charge.
He took part in the discovery of ten of the periodic table's chemical elements. Element 106 is named in his honor.