Chemistry Timeline

  • Democritus

    Democritus was one of the two founders of the ancient atomist theory. Discovering around 415 BC, he believed that matter is composed of empty space through which atoms move, and that the atoms are solid, homogeneous, indestructible, and indivisible. Different kinds of atoms have different sizes and shapes, which makes differences in their movements. Changes in matter result from changes in the grouping of atoms and not from changes in the atoms alone.
  • Aristotle

    As one of the most influential philosophers, Aristotle wrote extensively on many subjects including politics, ethics, nature, physics, and astronomy.While he was one of the most influential of his time -- 340 BC -- most of his writings have been lost through the ages.
  • Antoine Lavoisier

    Antoine Lavoisier
    A french scientist who was one of the first to use an analytical balance to monito chemical reactions. Studied the thermal decomposition of mercury, ocide, known then as calx of mercury.
  • Tricycle

    Two Frenchman, Blanchard and Maguier, invented the tricycle which was a three wheeled divice of transportation.
  • Joseph Proust

    Joseph Proust
    Based on his studies on copper carbonate reactions, Proust discovered that each pure compound has its own characteristic elemental composition. This spawned the Law of Definite Proportions that stated that the proportion by the masses of two given elements would always remain the same.
  • Egyptains

    In the 1800s Egyptains extracted pigments and made them into stains that were used as lipstick. Nowadays lipstick can be found in tubes in the solid form in hundreds of different shades.
  • John Dalton

    John Dalton
    John Dalton believed that all matter is composed extremely small particles called atoms, and that all atoms of a given element are identical, however, atoms of a different element are not the same. He said that in chemical reactions atoms can be separated, combines, or rearanged, and different atoms can combine in simple wholenumber ratios to form compounds. Atoms cannot be created, devided into smaller particles, or destroyed.
  • Amadeo Avagadro

    Amadeo Avagadro
    Determined to volume of one mole of a gas.
    602 000 000 000 000 000 000 000
  • Telephone

    Alexander Graham Bell spilled acid on himself and accidentally discovered the telephone.
  • Albert Spalding

    Albert Spalding
    Spalding is a sporting goods company that was invented in the year 1876, after the game of basketball was invented. They were the first to produce a so called "basketball" for the rising game.
  • Thomas Edison

    Thomas Edison
    In the year 1879, Thomas Edison invented the lightbulb which revolusionized the way we live today.
  • William Crooks

    William Crooks
    English physicist Sir William Crookes noticed a flash of light within one of the tubes while working in a dark lab one day. And so became the accidental discovery of the cathode ray. This in turn led to the development of the television.
  • J. J. Thomson

    J. J. Thomson
    The English physicist began a series of cathode ray tuve experiments to determine the ration of a particles charge to its mass by carefully measuring the effect of both magnetic and electric fields on a cathode ray. He then campared his ratios to others, concluding that the mass of the charged particle was much less than that of a hydrogen atom, which is the lightest known atom. Went against what Dalton said, there were smaller particles than the atom, the electron.
  • Henri Becquerel

    Studied minerals that emit light after being exposed to sunlight, which was a phenomenon called phosphorescence.
  • Madame Curie

    Madame Curie
    Discovered Polonium, a rare, radioactive, and extremely toxic metal, with her husband Pierre Curie. They named it for Marie's homeland, Poland.
  • Max Planck

    Max Planck
    German physicist that concluded that matter can gain or lose energy only in small, specific amounts called quanta.
  • Albert Einstein

    Albert Einstein
    Proposed that electromagnetic radiation has both wavelike and particlelike natures.
  • Henry Mosely

    Henry Mosely
    Mosely discovered that atoms of each element contain a unique positive charge in their nuclei. Therefore, the number of protons in an atom identifies it as an atom of a particular element, which is referred to as the element's atomic number.
  • Robert Millikan

    Robert Millikan
    The American physician Robert Millikan determined the charge of an electron. Even though it was descovered over one hundred years ago, it is within 1% of the accepted value today.
    mass of an electron = 9.1 * 10^-28g = 1/1840
    This raised questions of the nature of atoms. To try and answer these questions he proposed a model that became known as the plum pudding model.
  • Ernest Ruthurford

    Ernest Ruthurford
    By chance, Ernest recieved a scholarship to Cambridge University in England. By 1908 he won the Nobel Prize in chemistry and had many discoveries under his name. In 1911 Ernest became interested in alpha particles. Along with a small group of scientist they conducted an experiment to see if alpha paricles would be deflected as they passed throuhg a thin foil of gold. The expiriment was a success, and contrasted the plum pudding model, which was later concluded incorrect.
  • Neils Bohr

    Neils Bohr
    Proposed that the hydrogen atom has only certain allowable energy states.
  • Louis deBroglie

    Louis deBroglie
    Developing his idea that the electron is only allowed certain possible wavelengths, frequencies, and energies, he derived an equation.
    wavelength = height / mass*velocity
  • Werner Heisenberg

    Concluded that it is impossible to make any measurement on an object without disturbing the object at least a little.
  • Erwin Schrodinger

    Erwin Schrodinger
    Furthured the wave-particle theory proposed by de Broglie and derived and equation that treated the hydrogen atom's electron as a wave. The new model seemed to apply equally as well to atoms of other elements, to which Bohr's model fails.
  • James Chadwick

    James Chadwick
    A fellow coworker of Ruthurford, the English physicist James Chadwick showed that the nucleus also contained another subatomis particle. The particle was named a neutron, because it was neutral. Therefor, the three subatomic which are the fundamental building blocks from which all aroms are made had been discovered.
  • Caroline Davidson

    Caroline Davidson
    Davidson developed a clothing brand and named it NIKE, after the Greek goddess Nike. It was said that after a war was won in their favor, the warriors would thank Nike.
  • Cellphone

    Martin Cooper was the first to make a call on his own personal cellphone.
  • Personal Computer

    Personal Computer
    Steve Jobs and Steve Wozniak started the personal computer which led to easier ways of communication and also easier ways to learn information.
  • Solo Cup

    Solo Cup
    The solo cup was invented in the year 1978. Prior to these cups everyone drank out of communal cups which easily spread diseases.
  • Kevin Plank

    Kevin Plank
    Kevin Plank started the Under Armour brand in the year 1975 which revolutionized sports as we know them today. As a college athlete, Plank wanted to develop a fabric for athletes to make performance better. He succeeded when with Under Armour.