History of the Periodic Table: Difference between revisions

Almost all of the credit for the periodic table goes to Dmitri Mendeleev. He arranged the elements by their atomic mass, like Newlands, but he did something different. He added in the elements that had not been discovered yet. He decided to do this because while he was studying the atomic masses he noticed that when they were put in order some of them increased more than others. <ref name=BJU/> He also arranged them vertically <ref>BBC. [http://www.bbc.co.uk/schools/gcsebitesize/science/add_edexcel/atomic_structure/periodictablerev1.shtml Atoms and the periodic table] ''BBC Science''. Accessed May 21, 2017.</ref>, and added the transition metals. He recognized that the transition metals did not fit into the chart so he separated them from the rest of the periodic table. Mendeleev summarized his work by writing the periodic law. The law states, "The properties of elements vary with their atomic masses in a periodic way". <ref name=BJU/>