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The '''periodic table of the elements''' is a diagrammatic tool to illustrate the scientific [[theory]] of [[periodicity]] in [[chemistry]], in which the [[element]]s have similar properties based on their position on the table.  For example, the elements on the left of the table are all [[metal]]s.  The table has a lot of predictive power, although there are many exceptions to the periodic properities.

The '''periodic table of the elements''' is a diagrammatic tool to illustrate the scientific [[theory]] of [[periodicity]] in [[chemistry]], in which the [[element]]s have similar properties based on their position on the table.  For example, the elements on the left of the table are all [[metal]]s.  The table has a lot of predictive power, although there are many exceptions to the periodic properities.

The periodic table was first developed by [[Russia|Russian]] [[chemistry|chemist]] [[Dimitri Mendeleev]]. Its layout accurately arranges elements by their [[electron]] configuration, atomic number, and chemical properties. Using the structure he created, Mendeleev predicted the existance and properties of several yet-undiscovered elements; when the corresponding elements were discovered, his estimates proved to be quite accurate.

The periodic table was first developed by [[Russia|Russian]] [[chemistry|chemist]] [[Dimitri Mendeleev]]. Its layout accurately arranges elements by their [[electron]] configuration, atomic number, and chemical properties. Using the structure he created, Mendeleev predicted the existance and properties of several yet-undiscovered elements; when those elements were discovered, his estimates proved to be quite accurate.

[[Image:Periodic_table.jpg|thumb|center|750px|Periodic Table of the Elements]]

[[Image:Periodic_table.jpg|thumb|center|750px|Periodic Table of the Elements]]