-
450 BCE
Democritus
He proposed the fact that everything made up of little blocks invisible to the eye. https://historyofatomictheory.weebly.com/democritus.html -
427 BCE
Plato
He proposed that atoms break down into geometric forms like triangles. https://findanyanswer.com/when-did-plato-discover-the-atom -
500
The Alchemists
The Alchemists found the foundation of the modern-day periodic Table. https://philosophy-question.com/library/lecture/read/397301-what-did-the-alchemists-contribute-to-the-atomic-theory#:~:text=What%20did%20the%20alchemists%20contribute%20to%20the%20atomic,the%20Modern%20Day%20Periodic%20Table%20of%20the%20elements. -
Robert Boyle
He thought that atoms were small universal particles that were only different in shape and motion.
https://www.britannica.com/biography/Robert-Boyle -
Antoine Lavoisier
Antoine Lavoisier proposed the Law of conservation which changed how people viewed the atom. https://healthresearchfunding.org/antoine-lavoisier-and-the-atomic-theory/ -
John Dalton
He made up the Billiard Ball model of the atom and the atomic theory of matter that we still use today. http://thehistoryoftheatom.weebly.com/john-dalton.html -
Amedeo Avogadro
After he figure out that equal volumes of gases at the same temperature and pressure have the same number of molecules, he used this knowledge to relies that water was made up of 1 oxygen and 2 hydrogens. https://theatomictheoryandchemists.weebly.com/amedeo-avogadro.html -
JJ Thompson
He thought that the atom was a positive charged sphere with negative charged electrons in it and this model of the atom was called the Plum Pudding Model.
https://byjus.com/chemistry/thomsons-model/ -
Pierre and Marie Curie
They discover the existence of radium and polonium and other radioactive elements. https://easierwithpractice.com/how-did-marie-and-pierre-curie-contribute-to-the-atomic-theory/ -
Albert Einstein
He was the first person to prove that atoms exist using a microscope. https://www.ans.org/news/article-969/albert-einstein-and-the-most-elemental-atomic-theory/ -
Dmitri Mendeleev
He created the first periodic table of elements that we still use as a tool today. https://seanseanc96.wixsite.com/atomic-theory/mendeleev -
Ernest Rutherford
He made the Electron Cloud atomic model with a nucleus and electrons that just went all around the nucleus. https://atomictheoryfinal.weebly.com/ernest-rutherford.html -
Neils Bohr
He found out that that electrons were orbiting the nucleus. https://atomictheoryfinal.weebly.com/niels-bohr.html -
Henry G. J. Mosely
He founded Mosley's law that said that frequencies are proportional to the squares of whole numbers that are equal to the atomic number plus a constant.
https://www.britannica.com/biography/Henry-Moseley -
Robert Millikan
He discovered the charge and value of a single electron. https://robertmillikan.wordpress.com/2013/02/27/atomic-theory/ -
Werner Heisenberg
He founded the Uncertainty principle that said that no particle, atom or object has definite momentum, trajectory or position. https://werner-heisenberg.weebly.com/contribution-to-the-atom.html
https://www.atomicheritage.org/profile/werner-heisenberg -
Erwin Schrodinger
He made a formula that calculated the levels of electrons orbiting on any atom on the periodic table. https://atomictheoryproject10.weebly.com/erwin-schrodinger.html -
James Chadwich
He discovered the neutron in the atom and came up with the Solar System model.
https://study.com/learn/lesson/james-chadwick-atomic-theory-experiment.html