-
500 BCE
The Alchemists
Alchemy contributed to the atomic theory by laying the foundation of the modern day periodic table. https://www.britannica.com/science/chemistry/Alchemy -
427 BCE
Plato
Introduced the atomic theory in which the geometric forms serve as atoms.
http://abyss.uoregon.edu/~js/glossary/plato.html#:~:text=Plato%20was%20so%20impressed%20with%20this%20discovery%20that,Plato%20postulated%20that%20a%20fifth%20atomic%20type%20must -
400 BCE
Democritus
Democritus adopted the atomic theory and developed it further. "Everything is made up of atoms which are physically invisible. He also created the first atomic model.
https://www.britannica.com/biography/Democritus -
Robert Boyle
He helped develop a definition of an element. He created the Boyle law which states that if volume of a gas is decreased, the pressure increases proportionally.
https://www.bbc.co.uk/history/historic_figures/boyle_robert.shtml -
Antoine Lavoisier
Lavoisier found that mass is conserved in a chemical reaction. "Law of Conservation of mass."
https://philosophy-question.com/library/lecture/read/307569-what-are-the-contributions-of-antoine-lavoisier -
John Dalton
He was the 1st scientist to explain the behavior of atoms in terms of their measurement and weight. He also created the Billiard Ball model because he envisioned them as small hard spheres, so he used wooden balls to model them.
janetpanic.com/what-was-john-dalton-contribution-to-chemistry/ -
Dmitri Mendeleev
He was the most important contributor of the 1st periodic table of elements.
https://www.britannica.com/biography/Dmitri-Mendeleev -
Pierre and Marie Curie
They discovered that the atoms themselves were radioactive specifically polonium and radium which were strongly radioactive.
https://www.britannica.com/science/atom/Discovery-of-radioactivity -
JJ Thompson
He proposed a model called Plum Pudding model which played an important role of the research of an atomic structure.
https://www.khanacademy.org/science/chemistry/electronic-structure-of-atoms/history-of-atomic-structure/a/discovery-of-the-electron-and-nucleus -
Albert Einstein
He proved the atoms existence through Brownian motion and also created the atomic bomb.
https://www.ans.org/news/article-969/albert-einstein-and-the-most-elemental-atomic-theory/ -
Robert Millikan
Millikan was able to precisely calculate the magnitude of the electron's charge and also deduced the electric charge of an electron. https://www.nobelprize.org/prizes/physics/1923/millikan/biographical -
Ernest Rutherford
He changed the atomic model because of his gold foil experiment. He used alpha particles emitted by radioactive probes to the unseen world of the atomic structure.
https://www.britannica.com/biography/Ernest-Rutherford -
Neils Bohr
Bohr developed the Bohr model of the atom which introduced quantum mechanics, and also made the Solar system atomic model.
https://www.britannica.com/biography/Niels-Bohr -
Henry G. J Mosely
He discovered the atomic number of each element using x-rays which led to a more accurate organization of the periodic table. www.britannica.com/science/Moseleys-law -
Erwin Schrodinger
He made an equation that pinpointed were atoms were which helped in making very accurate models of atoms. He also created the electron cloud.
https://www.britannica.com/biography/Erwin-Schrodinger -
James Chadwick
He discovered the neutrons in atoms and that they are located in the center of an atom.
https://www.britannica.com/biography/James-Chadwick
