PRESENTATION OUTLINE
Contributions:
Dobereiner discovered that the relative atomic mass of the middle element in each triad was close to the average of the relative atomic masses of the other two elements. This gave other scientists a clue that relative atomic masses were important when arranging the elements.
Contributions:
Development of a rational system of atomic symbols
Contributions:
Proposed that elements repeated their chemical properties every 8 chemicals
Contributions:
In about 1868 Meyer prepared an expanded table, similar in many ways to Mendeleyev’s table published in 1869. It was not until 1870, however, that Meyer published his own table, a graph relating atomic volume and atomic number and clearly showing the periodic relationships of the elements.
Contributions:In 1869, just five years after John Newlands put forward his Law of Octaves, a Russian chemist called Dmitri Mendeleev published a periodic table. Mendeleev also arranged the elements known at the time in order of relative atomic mass, but he did some other things that made his table much more successful.
