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: Mendeleev was a [[scientist]] who made the modern first successfull [[Periodic Table]].

: Many people had attempted to arrange the [[element]]s into a table before [[Mendeleev]] but [[Mendeleev]] was the first to combine [[Chemical Property|chemical properties]] and [[Relative Atomic Mass|atomic mass]] into one table.: The modern [[Periodic Table]] is based on [[Mendeleev]]'s with one modification. It is based on the [[Atomic Number]] and [[Chemical Property|chemical properties]], not the [[Relative Atomic Mass|atomic mass]].