History of the Atomic Theory

By Ponchoglezh
  • 460 BCE

    Birth of Democritus

    This year, the person who would come up with the first theory of the atoms was born.
  • Period: 460 BCE to 370 BCE

    Lifespan of Democritus

  • 450 BCE

    Theory of the 4 elements

    Greek philosophers created the theory that everything was made by the 4 elements: fire, earth, air, and water. This theory then was approved by Aristotle
  • 420 BCE

    First theory of the atom

    This year, Democritus came up with the first theory.
  • Period: 382 BCE to 322 BCE

    Lifespan of Aristoteles

  • 370 BCE

    Death of Democritus

    This year, Democritus died.

  • Industrial Revolution

    The industrial revolution comes with new changes and advantages that contribute to the known elements.
  • Period: to

    Lifespan of John Dalton

  • Law of conservation of mass.

    In this year, Lavoisier discovered the Law of conservation of mass which states that matter can nor be destroyed nor created, it can only transform.

  • John Dalton`s atomic theory

    He continued Democritus's idea by some experiment he made during the french revolution. He continued the idea that all matter were made of atoms and concluded with the Law of Mass Conservation.

  • Mexican independence

    Mexico gains independence from Spain
  • Period: to

    Lifespan of Lothar Meyer

  • Period: to

    Lifespan of Dimitri Mendeleev

  • Period: to

    Lifespan of John Newlands

  • Organization for change in Discovering atomic mass.

    Scientists organize each other to finally make a strategy to correctly determine the atomic mass.

  • New organizational scheme for elements.

    John Newlands proposes a new way to organize elements in a scheme by increasing atomic mass.

  • Shown connections of atomic mass and properties of elements.

    The scientists Mendeleev and Meyer show the connection between atomic mass and properties of elements. Mendeleev`s way of organizing by increasing order was highly accepted.

  • 60 known element

    Know there are 60 known elements since Lavoisier`s first edition of it.
  • Period: to

    Lifespan of Henry Moseleyu

  • Electron discovered

    Joseph John Thomson discovered the negatively charged electron.

  • William Thomson atomic theory

    In this year William Thomson with the cookie chip model, that was an atom with negatively charged electrons.

  • Mexican Revolution

    Mexico fights its war for a new government

  • Rutherford Atomic Theory

    In this year Rutherford concluded that the cell had only a little space a nucleus that had mass.

  • Bohr atomic Theory

    Proposed the theory of atoms having a nucleus and rings going around them as planets.

  • Moseley`s investigation on periodic law.

    Moseley makes the periodic law which states the correct order of the periodic table as we know it today.

  • Mexico has 3 presidents in the same day.

    Francisco I. Madero Gonzàlez, Pedro Lascuaràin Hernandez and Victoriano Huerta were presidents of Mexico in the same day

  • WWI

    First world war is declared, Germany invades Belgium.
  • Period: to

    The Great War

  • Heisenberg Nobel Prize

    Wins Nobel prize of his theory on the speed of atoms.

  • James Chadwick and neutron

    Introduces the term neutron.

  • WWII

    Start of world war two; Germany invades Poland