Timeline of the Atom

By Cydney
  • 370

    Area Under a Curve Determined

    Area Under a Curve Determined
    Eudoxus of Cnidus comes up with the method of exhaustion for mathematically determining the area under a curve.
  • 384

    Aristotle

    Aristotle
    Came up with his theory of matter which stated that he believed there were only five elements: air, earth, water, fire, and aether. He was later proven wrong, but he did help the progression of the scientific community by saying that there are elements.
  • 400

    Catapult is Invented

    Catapult is Invented
    Catapult video
    Greek engineers invent the catapult. Which is a weapon used to launch objects long distances.
  • 460

    Democritus

    Democritus
    Claimed that everything is made up of atoms. That between atoms lies empty space, atoms are indestructible, will always be in motion, and there is an infinite number of atoms. He reasoned that the solidness of a material corresponded with the type of atom involved.
  • Antoine Lavoisier

    Antoine Lavoisier
    Known for experimental skills. Used his experiments to come up with the Law of Conservation, the law that states that matter cannot be made or destroyed. He also mentioned the rearrangement of matter in reactions.
  • Joseph Proust

    Joseph Proust
    Proust proved that substances always combine in constant and definite proportions. His largest accomplishment was creating other elements from water.
  • U.S. Declares Independence from Great Britain

    U.S. Declares Independence from Great Britain
    The thirteen original U.S. colonies, at war with Great Britain at the time, announces they are no longer part of the British Empire. Instead they formed a union to become a new nation. John Adams was the leader of the movement, but there were others including: Benjamin Franklin and Thomas Jefferson.
  • Amadeo Avogadro

    Amadeo Avogadro
    Came up with the law: equal volumes of gases at the same temperature and pressure contain the same number of molecules regardless of their chemical nature and physical properties.
  • John Dalton

    John Dalton
    Atomic theory was based on atoms of different elements could be distinguished by their weight. Basic ideas of his theory: All matter composed of atoms, can't be created or destroyed, atoms of the same element are identical, different elements have different types of atoms, chemical reactions occur when atoms are rearranged.
  • Storming of the Bastille

    Storming of the Bastille
    Originally meant to be a fortress. It was stormed by a crowd during the French Revolution. It became an important symbol for the French Republican movement.
  • William Crookes

    William Crookes
    Discovered cathode rays had the following properties: travel in straight lines, cause glass to fluoresce, put a negative charge on objects they strike, are deflected by electric fields and magnets to suggest a negative charge, they cause pinwheels in their path to spin leading us to believe they have mass.
  • Henri Becquerel

    Henri Becquerel
    Worked with others to discover radioactivity. While studying the effect of x-rays on photographic film, he discovered some chemicals spontaneously decompose and give off dangerous rays (radioactivity).
  • J. J. Thomson

    J. J. Thomson
    In 1897, showed that cathode rays were composed of a previously unknown negatively charged particle. So he was given credited with the discovery and identification of the electron.
  • Max Planck

    Max Planck
    He originated quantum theory, which is now a huge part of 20th century physics along with Albert Einstein's work.
  • Madame Curie

    Madame Curie
    She studied uranium and thorium and called their spontaneous decay process "radioactivity". She and her husband also discovered the radioactive elements polonium and radium.
  • Robert Millikan

    Robert Millikan
    His oil drop experiment determined the charge and the mass of an electron. He proved that this was the same for all electrons, so in turn he demonstrated the atomic structure of electricity.
  • First Motion Picture

    First Motion Picture
    Motion picture of a horse and rider
    First motion picture is shown to a theatre audience in Philedelphia, Pennsylvania. It was a silent film and was also in black and white.
  • Ernest Rutherford

    Ernest Rutherford
    Described the atom as having a central postivie nucleus that is surrounded by negative orbiting electrons. his model suggested that most of the mass of an atom was in the nucleus.
  • Albert Einstein

    Albert Einstein
    Developed the general theory of relavtivity. In 1917 applied the general theory of relativity to model the large-scale structure of the universe.
  • Patent of the Lamp

    Patent of the Lamp
    Thomas Edison patents his electric incandesent lamp. The lamp provided light to people so they could see in the dark after the sun had set.
  • Niels Bohr

    Niels Bohr
    Most important contribution to modern physics was his atomic model. He was the first to discover that electrons travel in separate orbits around the nucleus and that the number of electrons in the outer orbit determine the element.
  • Erwin Schrodinger

    Erwin Schrodinger
    Formed the basis of wave mechanics and formulated the wave equation during his work in the field of quantum theory. His most famous thought experiment was Schrodinger's cat.
  • Henry Moseley

    Henry Moseley
    Came up with the concept of the atomic number. Developed Moseley's law which justified many concepts in chemistry by sorting the chemical elements of the periodic table into a logical order based on their physics.
  • James Chadwick

    James Chadwick
    Using alpha particles, he discovered a neutral atomic particle with a mass close to a proton. This was the neutron.
  • Louis de Broglie

    Louis de Broglie
    He discovered that electrons had a wave nature, and suggested that all matter have wave properties.
  • Werner Heisenberg

    Werner Heisenberg
    Discovered the Uncertainty Principle which states that electrons don't travel in neat orbits and all electrons contain photons that change momentum and physics. His contribution to the atomic theory was that he calculated the behavior of electrons and subatomic particles that also make up an atom.
  • World War I

    World War I
    Trench Warfare in WWI
    Global war centered in Europe. It began when a serbian assasinated the archduke of Austria, which then pitted the Central powers against the Allied powers.
  • Lie Detector

    Lie Detector
    John Larsen invents the lie detector. This device was used on criminals and people suspected to be spys.
  • Amelia Earhart

    Amelia Earhart
    Amelia Earhart
    Earhart becomes the first woman to fly solo across the Atlantic.
  • Rise of Adolf Hitler

    Rise of Adolf Hitler
    Adolf Hitler speeches
    Hitler joined the political party called the NSDAP (Nazi party). This party wanted to unite all German speaking countries, and they were also anti--Semitism. He worked his way to the top of the party in the beginning of his career, because he was such a fantastic speaker.