In this video explains Periodic Classification of Elements : In the last lesson you have studied about the structure of atoms and their electronic configurations. You have also studied that elements with similar electronic configurations show similar chemical properties. Electrons are filled in various shells and sub shells in a fairly regular fashion. Therefore, properties of elements are repeated periodically. Such trends in their physical and chemical properties were noticed by chemists in the nineteenth century and attempts were made to classify elements on their basis long before structure of atom was known. In this lesson we shall study about the earlier attempts for classification, the first successful classification which included all the known elements at that time namely Mendeleev’s periodic table, and about the long form of modern periodic table which is an improvement over Mendeleev’s work. Finally we shall learn about some properties of elements and their variations in the periodic table.

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