ATOMIC THEORIST TIMELINE

01

Antoine Lavoisier

Antoine Lavoisier discovered the law of conservation of mass, named "oxygen", and helped systematize chemical nomenclature. These events occurred between 1772 to 1794. Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.“Lavoisier.” Purdue.edu, 2019, chemed.chem.purdue.edu/genchem/history/lavoisier.html. Picture Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.

02

Joseph proust

Joseph Proust discovered Proust's law or law of definite proportions in 1793. Proust's law is relative quantities of any given pure chemical compound that's constituent element remains invariant, regardless of the compound’s source. Citation(s): “Joseph-Louis Proust | French Chemist.” Encyclopædia Britannica, 2019, www.britannica.com/biography/Joseph-Louis-Proust. Picture Citation(s): “Michael Crichton Film Series – Andromeda Strain.” Linda Hall Library, 26 Sept. 2018, www.lindahall.org/joseph-proust/.

03

john dalton

In 1804, John Dalton discovered an atomic theory of matter. Citation(s): “John Dalton.” Science History Institute, 31 Jan. 2018, www.sciencehistory.org/historical-profile/john-dalton. Usselman, Melvyn C., et al. “Dalton’s Disputed Nitric Oxide Experiments and the Origins of His Atomic Theory.” ChemPhysChem, vol. 9, no. 1, 11 Jan. 2008, pp. 106–110, 10.1002/cphc.200700707. Picture Citation(s): “John Dalton.” Science History Institute, 31 Jan. 2018, www.sciencehistory.org/historical-profile/john-dalton.

04

Dmitri Mendeleer

On February 17, 1869, Dmitri Mendeleev arranged elements in order of its increasing atomic weight. Citation(s): Bensaude-Vincent, Bernadette. “Dmitri Mendeleev | Biography & Facts.” Encyclopædia Britannica, 2019, www.britannica.com/biography/Dmitri-Mendeleev.“Dmitri Mendeleev.” New Scientist, 2019, www.newscientist.com/people/dmitri-mendeleev/. Picture Citation(s): Bensaude-Vincent, Bernadette. “Dmitri Mendeleev | Biography & Facts.” Encyclopædia Britannica, 2019, www.britannica.com/biography/Dmitri-Mendeleev.

05

henri becquerel

On March 1, 1896, while Henri Becquerel was investigating X-rays, Becquerel by accident discovered that uranium salts emit penetrating radiations that can be seen on photographic plates. Citation(s): “The Nobel Prize in Physics 1903.” NobelPrize.org, 2019, www.nobelprize.org/prizes/physics/1903/becquerel/facts/. This Month in Physics History.” @Apsphysics, 2019, www.aps.org/publications/apsnews/200803/physicshistory.cfm. Picture Citation(s): Long, Tony. “March 1, 1896: All Aglow.” Wired, 1 Mar. 2011, www.wired.com/2011/03/0301becquerel-discovers-radioactivity/.

atomic theorist TIMELINE

between 1772 and 1794

Antoine Lavoisier discovered the law of conservation of mass, named "oxygen", and helped systematize chemical nomenclature. These events occurred between 1772 to 1794. Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.“Lavoisier.” Purdue.edu, 2019, chemed.chem.purdue.edu/genchem/history/lavoisier.html. Picture Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.

1804

Antoine Lavoisier discovered the law of conservation of mass, named "oxygen", and helped systematize chemical nomenclature. These events occurred between 1772 to 1794. Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.“Lavoisier.” Purdue.edu, 2019, chemed.chem.purdue.edu/genchem/history/lavoisier.html. Picture Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.

1793

Antoine Lavoisier discovered the law of conservation of mass, named "oxygen", and helped systematize chemical nomenclature. These events occurred between 1772 to 1794. Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.“Lavoisier.” Purdue.edu, 2019, chemed.chem.purdue.edu/genchem/history/lavoisier.html. Picture Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.

1869

Antoine Lavoisier discovered the law of conservation of mass, named "oxygen", and helped systematize chemical nomenclature. These events occurred between 1772 to 1794. Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.“Lavoisier.” Purdue.edu, 2019, chemed.chem.purdue.edu/genchem/history/lavoisier.html. Picture Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.

1896

Antoine Lavoisier discovered the law of conservation of mass, named "oxygen", and helped systematize chemical nomenclature. These events occurred between 1772 to 1794. Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.“Lavoisier.” Purdue.edu, 2019, chemed.chem.purdue.edu/genchem/history/lavoisier.html. Picture Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.

Lorem ipsum dolor sit amet, consectetur dipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam.

Lorem ipsum dolor sit amet, consectetur dipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam.

Lorem ipsum dolor sit amet, consectetur dipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.

06

marie curie

In 1898, Marie Curie discovered two new radioactive elements that being, radium, and polonium. Curie also contributed by finding treatments for cancer. Citation(s): Marie Curie. “Marie Curie the Scientist | Biog, Facts & Quotes.” Marie Curie, 2016, www.mariecurie.org.uk/who/our-history/marie-curie-the-scientist. "The Nobel Prize in Physics 1903.” NobelPrize.org, 2019, www.nobelprize.org/prizes/physics/1903/marie-curie/questions-and-answers/. Picture Citation(s): Marie Curie. “Marie Curie the Scientist | Biog, Facts & Quotes.” Marie Curie, 2016, www.mariecurie.org.uk/who/our-history/marie-curie-the-scientist.

07

max planck

In 1900, Max Planck discovered the quantum of action or also known as Planck's constant. Citation(s): Stuewer, Roger H. “Max Planck | Biography, Discoveries, & Quantum Theory.” Encyclopædia Britannica, 30 Sept. 2018, www.britannica.com/biography/Max-Planck. Picture Citation(s): Stuewer, Roger H. “Max Planck | Biography, Discoveries, & Quantum Theory.” Encyclopædia Britannica, 30 Sept. 2018, www.britannica.com/biography/Max-Planck.

08

robert millikan

In 1910, Robert Millikan discovered the elementary charge of an electron when doing an oil-drop experiment. Citation(s): “Robert Millikan.” Nasonline.org, 2019, www.nasonline.org/member-directory/deceased-members/20001580.html. "The Nobel Prize in Physics 1923.” NobelPrize.org, 2019, www.nobelprize.org/prizes/physics/1923/millikan/facts/. Picture Citation(s): “Robert Millikan.” Nasonline.org, 2019, www.nasonline.org/member-directory/deceased-members/20001580.html.

09

ernest rutherford

In 1911, Ernest Rutherford discovered both the nucleus of the atom and alpha and beta rays. Citation(s): "Ernest Rutherford.” Science History Institute, 11 Jan. 2018, www.sciencehistory.org/historical-profile/ernest-rutherford. "Rutherford’s Nuclear World: The Story of the Discovery of the Nucleus | Sections | American Institute of Physics.” History.aip.org, history.aip.org/exhibits/rutherford/sections/alpha-particles-atom.html#:~:text=Ernest%20Rutherford%20discovered%20the%20nucleus. Picture Citation(s): Ernest Rutherford.” Science History Institute, 11 Jan. 2018, www.sciencehistory.org/historical-profile/ernest-rutherford.

10

atomic theorist TIMELINE

henry moseley

In 1913, Henry Moseley discovered Moseley's law which related to atomic numbers. Citation(s): "Atomic Number | Definition & Facts | Britannica.” Encyclopædia Britannica, 2019, www.britannica.com/science/atomic-number. Picture Citation(s): LaFollette, Marcel Chotkowski. “Science Service, up Close: Two Haunting Portraits of Henry Gwyn Jeffreys Moseley.” Smithsonian Institution Archives, 7 Nov. 2019, siarchives.si.edu/blog/science-service-close-two-haunting-portraits-henry-gwyn-jeffreys-moseley. Accessed 28 Aug. 2021.

1898

In 1900, Max Planck discovered the quantum of action or also known as Planck's constant. Citation(s): Stuewer, Roger H. “Max Planck | Biography, Discoveries, & Quantum Theory.” Encyclopædia Britannica, 30 Sept. 2018, www.britannica.com/biography/Max-Planck. Picture Citation(s): Stuewer, Roger H. “Max Planck | Biography, Discoveries, & Quantum Theory.” Encyclopædia Britannica, 30 Sept. 2018, www.britannica.com/biography/Max-Planck.

1900

In 1900, Max Planck discovered the quantum of action or also known as Planck's constant. Citation(s): Stuewer, Roger H. “Max Planck | Biography, Discoveries, & Quantum Theory.” Encyclopædia Britannica, 30 Sept. 2018, www.britannica.com/biography/Max-Planck. Picture Citation(s): Stuewer, Roger H. “Max Planck | Biography, Discoveries, & Quantum Theory.” Encyclopædia Britannica, 30 Sept. 2018, www.britannica.com/biography/Max-Planck.

1910

In 1900, Max Planck discovered the quantum of action or also known as Planck's constant. Citation(s): Stuewer, Roger H. “Max Planck | Biography, Discoveries, & Quantum Theory.” Encyclopædia Britannica, 30 Sept. 2018, www.britannica.com/biography/Max-Planck. Picture Citation(s): Stuewer, Roger H. “Max Planck | Biography, Discoveries, & Quantum Theory.” Encyclopædia Britannica, 30 Sept. 2018, www.britannica.com/biography/Max-Planck.

1911

In 1900, Max Planck discovered the quantum of action or also known as Planck's constant. Citation(s): Stuewer, Roger H. “Max Planck | Biography, Discoveries, & Quantum Theory.” Encyclopædia Britannica, 30 Sept. 2018, www.britannica.com/biography/Max-Planck. Picture Citation(s): Stuewer, Roger H. “Max Planck | Biography, Discoveries, & Quantum Theory.” Encyclopædia Britannica, 30 Sept. 2018, www.britannica.com/biography/Max-Planck.

1913

Antoine Lavoisier discovered the law of conservation of mass, named "oxygen", and helped systematize chemical nomenclature. These events occurred between 1772 to 1794. Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.“Lavoisier.” Purdue.edu, 2019, chemed.chem.purdue.edu/genchem/history/lavoisier.html. Picture Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.

Lorem ipsum dolor sit amet, consectetur dipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam.

Lorem ipsum dolor sit amet, consectetur dipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam.

Lorem ipsum dolor sit amet, consectetur dipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.

11

niels bohr

In 1913, Niels Bohr claimed that based on the quantum theory, an atom should only be able to have certain orbits around the nucleus. Citation(s): Aaserud, Finn. “Niels Bohr | Biography, Education, Accomplishments, & Facts.” Encyclopædia Britannica, 2019, www.britannica.com/biography/Niels-Bohr. THE NOBEL PRIZE. “The Nobel Prize in Physics 1922.” NobelPrize.org, 2019, www.nobelprize.org/prizes/physics/1922/bohr/facts/. Picture Citation(s): THE NOBEL PRIZE. “The Nobel Prize in Physics 1922.” NobelPrize.org, 2019, www.nobelprize.org/prizes/physics/1922/bohr/facts/.

12

louis de broglie

In 1924, Louis de Broglie discovered the quantum theory and for coming up with the idea that electrons should not be described as particles but as waves. Citation(s): Barbara Lovett Cline. “Louis de Broglie | French Physicist.” Encyclopædia Britannica, 15 Mar. 2019, www.britannica.com/biography/Louis-de-Broglie. "The Nobel Prize in Physics 1929.” NobelPrize.org, 2019, www.nobelprize.org/prizes/physics/1929/broglie/facts/ Picture Citation(s): The Nobel Prize in Physics 1929.” NobelPrize.org, 2019, www.nobelprize.org/prizes/physics/1929/broglie/facts/

13

werner heisenberg

"In 1925, Werner Heisenberg formulated a type of quantum mechanics based on matrices. In 1927 he proposed the "uncertainty relation", setting limits for how precisely the position and velocity of a particle can be simultaneously determined." Citation(s): "The Nobel Prize in Physics 1932.” NobelPrize.org, www.nobelprize.org/prizes/physics/1932/heisenberg/facts/. Picture Citation(s): "The Nobel Prize in Physics 1932.” NobelPrize.org, www.nobelprize.org/prizes/physics/1932/heisenberg/facts/.

14

erwin schrodinger

In 1926, Erwin Schrodinger made an equation that measured the energy levels of electrons in atoms. Citation(s): "The Nobel Prize in Physics 1933.” NobelPrize.org, 2019, www.nobelprize.org/prizes/physics/1933/schrodinger/facts/. Picture Citation(s): "The Nobel Prize in Physics 1933.” NobelPrize.org, 2019, www.nobelprize.org/prizes/physics/1933/schrodinger/facts/.

15

james chadwick

In 1932, James Chadwick discovered the neutron. Citation(s): "James Chadwick.” Atomic Heritage Foundation, 2000, www.atomicheritage.org/profile/james-chadwick Picture Citation(s): "James Chadwick.” Atomic Heritage Foundation, 2000, www.atomicheritage.org/profile/james-chadwick

atomic theorist TIMELINE

1913

Antoine Lavoisier discovered the law of conservation of mass, named "oxygen", and helped systematize chemical nomenclature. These events occurred between 1772 to 1794. Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.“Lavoisier.” Purdue.edu, 2019, chemed.chem.purdue.edu/genchem/history/lavoisier.html. Picture Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.

1924

Antoine Lavoisier discovered the law of conservation of mass, named "oxygen", and helped systematize chemical nomenclature. These events occurred between 1772 to 1794. Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.“Lavoisier.” Purdue.edu, 2019, chemed.chem.purdue.edu/genchem/history/lavoisier.html. Picture Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.

1926

Antoine Lavoisier discovered the law of conservation of mass, named "oxygen", and helped systematize chemical nomenclature. These events occurred between 1772 to 1794. Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.“Lavoisier.” Purdue.edu, 2019, chemed.chem.purdue.edu/genchem/history/lavoisier.html. Picture Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.

1925

Antoine Lavoisier discovered the law of conservation of mass, named "oxygen", and helped systematize chemical nomenclature. These events occurred between 1772 to 1794. Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.“Lavoisier.” Purdue.edu, 2019, chemed.chem.purdue.edu/genchem/history/lavoisier.html. Picture Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.

1932

Antoine Lavoisier discovered the law of conservation of mass, named "oxygen", and helped systematize chemical nomenclature. These events occurred between 1772 to 1794. Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.“Lavoisier.” Purdue.edu, 2019, chemed.chem.purdue.edu/genchem/history/lavoisier.html. Picture Citation(s): “Antoine-Laurent Lavoisier.” Science History Institute, 11 Dec. 2017, www.sciencehistory.org/historical-profile/antoine-laurent-lavoisier.

Lorem ipsum dolor sit amet, consectetur dipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam.

Lorem ipsum dolor sit amet, consectetur dipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam.

Lorem ipsum dolor sit amet, consectetur dipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.