Periodic table

TImeline of the periodic table

By SofiaGomez45
  • 440

    Democritus and Leucippus

    Democritus and Leucippus
    Democritus and Leucippus proppose the idea of the atom. An invisible particle that all matter is made of.

  • Hennig Brand

    Hennig Brand
    The first elemnt really discovered was in 1649 and it was Phosphorus (P) and it was discovered by Hennig Brand. Before people knew about different elements like Gold (Au) and Copper (Cu) but this was the first one truly discovered.

  • Robert Boyle

    Robert Boyle
    Robert boyle in 1661 defined that an element is a substance that can not be broken down into a simpler substance by a chemical reaction.

  • Antoine Lavoisier

    Antoine Lavoisier
    Antoine Lavoisier was one of the first or the first to make up a list of elements. The list had 33 elements and was between metals and non metals. He is considered to be the 'father of modern chemistry'.

  • Johann Dobereiner-Laws of Triads

    Johann Dobereiner-Laws of Triads
    Between 1817-1829 Johann Dobereiner began to find elments with simmalar or properites that were alike into three groups or triads. This happened when he saw that the atomic wieghts of strodium was halfway between calcium and barium.

  • Atomic wieghts

    Atomic wieghts
    IN 1862 a man by the name of A.E.Beguyer de Chancourtois was one of the first people to use the atomic wieghts. With that he showed the elements were arranged by there atomic weights.

  • John Newlands-Law of Octaves

    John Newlands-Law of Octaves
    A year after Beguyer discovered uses of the atomic weights a man named John Newlands propsed the law of Octaves. This law said that elements repeat themselves after every eighth element.

  • Lothar Meyer

    Lothar Meyer
    Lothar Meyer made the early version of the periodic table. This table had 28 different elements and in 1868 made an extened version o the table and was published in 1870.

  • Dmitri Mendeleev

    Dmitri Mendeleev
    In 1864 also made a periodic table him and Lothar meyer studied under the same teacher. HIs tabled frouped the elements based off of their similar chemical properties and left spaces open for new elemnts to placed in them.

  • Modern Peridoic Table

    Modern Peridoic Table
    IN 1940 the peridoic table of elments was updated by a man named Glenn T. Seaborg. He discovered the Transurium elements atomic numbers 94 to 100. Both the lanthanide and the actinide series were placed under the periodic table.