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Evolution of Chemistry

By imruben
  • Period: 300 to

    Medieval Alchemy

    Reference300BC - End of 17th century Medieval Alchemy was the equivalent of chemistry in modern age. Alchemists believed that all matters were made up of main four elements (air, water, fire, earth). By combining those elements, alchemists were able to form any substance. Every alchemist's goal was discover the "philosopher stone". The stone was believed to have the power to turn cheap objects into gold and to make an elixer of immortality. Alchemy was also used as form of potions and medicine.
  • 430

    Democritus

    Democritus
    430 BC Democritus was an ancient Greek philisopher who proclaimed that all matter was composed of atoms and the atom to be the simplest unit of matter (first ever atomic theory). http://www.timelineindex.com/content/view/1228

  • John Dalton

    John Dalton
    John Dalton was originally a meteorologist. He had several handicaps. He was poor, he was not articulate, he was not a skilled experimentalist, and he was color blind. However, John Dalton was able to publish his Atomic Theory which states that all matter is composed of atoms, which are small and indivisible. http://www.chemistryexplained.com/Co-Di/Dalton-John.html

  • Henri Becquerel

    Henri Becquerel
    Henri came from a long bloodline of physcist. He was the first to discover radioactivity through his investigation of uranium and other substances. http://nobelprize.org/nobel_prizes/physics/laureates/1903/becquerel-bio.html

  • J.J Thompson

    J.J Thompson
    Thompson was the first person to suggest the theory of the atom containing positive and negative particles. He demonstrated the latter which he called electrons, experimented with cathode ray tubes to show how electron beams were deflected by magnetic forces and showed that the hydrogen atom has one electron. http://nobelprize.org/nobel_prizes/physics/laureates/1906/thomson-bio.html

  • Marie and Pierre Curie

    Marie and Pierre Curie
    Husband and wife worked together following Henri Becqerel's theoreom that elements emit radioactivity, Together they discovered both radium and polonium. Their discoveries later helped to fight cancer and tumors. Unfortunately Marie died due to leukemia which is caused by radioactivity. Marie was killed by her passion. http://nobelprize.org/nobel_prizes/physics/articles/curie/

  • Ernest Rutherford

    Ernest Rutherford
    Rutherford proposed a new model for the atom. He was the first to show that the atom must consist of a very tiny positively charged nucleus surrounded by negatively charged electrons. He also discovered and named alpha, beta and gamma radiation. http://nobelprize.org/nobel_prizes/chemistry/laureates/1908/rutherford-bio.html

  • Neils Bohr

    Neils Bohr
    Bohr became an apprentice of J.J Thompson and Ernest Rutehrford. Through their guidance, Bohr was able to publish his theory that electrons travel in orbits around the nucleus similar to the solar system. His "planetary" model of the atom is called "Bohr Model". http://www.helium.com/items/1681812-the-contributions-of-neils-bohr-to-chemistry

  • J. Chadwick

    J. Chadwick
    Intrigued by Rutherford's discoveries, James Chadwick was the first man to discover the neutron, the neutrally charged particle of the nucleus (which also contains protons, positively charged particles and the heaviest part of the atom). He also proposed that electrons travel around the nucleus on "orbits". http://www.vzhang.com/vzfiles/james_chadwick.htm