Dmitri Mendeleev's Periodic Law

He formulated the Periodic Law, created his own version of the periodic table of elements, and used it to correct the properties of some already discovered elements and also to predict the properties of eight elements yet to be discovered. Periodic Law card included with 3D Forever In 1863 there were 56 known elements with a new element being discovered at a rate of approximately one per year. Other scientists had previously identified periodicity of elements, notably Alexandre-Emile Béguyer de Chancourtois, seven years earlier, arranging the elements then known in a helix, three-dimensional barber pole style.
Periodic Law card included with 3D Forever
John Newlands described a Law of Octaves in 1864, also noting their sequence and periodicity according to relative atomic weight, publishing it in 1865. His proposal identified the potential for new elements such as germanium. The concept was criticized by his peers and his innovation was not recognized by the Society of Chemists until 1887.
Periodic Law card included with 3D Forever
Another person to propose a periodic table was Lothar Meyer, who published a paper in 1864 describing 28 elements classified by their valence, but with no prediction of new elements.
Periodic Law card included with 3D Forever
In a paper presented by him at the Theatre of the Royal Institution, June 4th, 1889, Mendeleev quoted his earlier conclusions, starting with "1. The elements, if arranged according to their atomic mass, exhibit an apparent periodicity of properties", and continued with seven other parameters.
Whats that, she said, the periodic table the way it's supposed to be but isnt?

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