Imgres

bb's big time line

  • Jan 1, 1000

    Democritus

    was the first person to propose the idea that matter was not infinitely divisble in 460-370 b.c
  • Jan 1, 1000

    Aristotle

    in 322-384 b.c he was able to gain wide acceptance for his idea on nature
  • joseph proust

    joseph proust
    Based on his studies on copper carbonate reactions, Proust discovered that each pure compound has its own characteristic elemental composition
  • John dalton

    John dalton
    revived and revised Democritus’s ideas based upon the results of
    scientific research he conducted.
  • amadeo avagadro

    amadeo avagadro
    states that equal volumes of gases, at the same temperature and pressure, contain the same number of molecules. Avogadro's hypothesis wasn't generally accepted until after 1858 (after Avogadro's death), when the Italian chemist Stanislao Cannizzaro was able to explain why there were some organic chemical exceptions to Avogadro's hypothesis.
  • Antoine Lavoisier

    Antoine Lavoisier
    compiled a list of elements known at the time
  • Charles Goodyear

    he heated a mixture of rubber and sulfur creating the rubber for tires
  • henri Antoine

    henri Antoine
    is known for his discovery of radioactivity
  • J.J Thomson

    began a series of cathode ray tube experiments
  • Max Planck

     Max Planck
    His study of the phenomenon led him to a startling conclusion: matter can gain or lose energy only in small, specific amountscalled quante
  • Robert Millikan

    determined the charge of an electron
  • Ernest Rutherford

    he was interested in studying how positively charged
    alpha particles (radioactive particles you will learn more about later in this
    chapter) interacted with solid matter
  • Henry Mosele

     Henry Mosele
    discovered that atoms of each element contain a uniquepositive charge in their nuclei
  • ErwinSchrödinger

    ErwinSchrödinger
    furthered the wave-particle theory proposed by de Broglie. Schrödinger derived an equation that treated the hydrogen atom’s electron as a wave
  • James Chadwick

    showed that the nucleus also contained another subatomic particle, a neutral particle called the neutron
  • Louis de Broglie

     Louis de Broglie
    De Broglie had been thinking that Bohr’s quantized electron orbits had characteristics similar to those of waves
  • william Crookes

    discovered the cathode ray led to the invention of one of the most important technological and social developments of
    the 20th century—the television.
  • madama curie

    madama curie
    discovered the radioactive substances of radium and polonium
  • Werner Heisenber

     Werner Heisenber
    a contemporary of de Broglie, proved to have profound implications for atomic models.
  • Albert Einstein

     Albert Einstein
    proposed in 1905 that electromagnetic radiation has both wavelike and particlelike natures
  • Niels Bohr

     Niels Bohr
    proposed a quantum model for the hydrogen atom that seemed to answer this question.
  • Antoine Lavoisier

    Antoine Lavoisier
    hat weight was conserved through the course of chemical reactions even those involving gases