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Unit: Periodic classification of elements

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About this unit

Learn how the periodic table organizes the known elements of our world. In this unit, we will learn about the history of the periodic classification of elements, Mendeleev's periodic law, its merits and demerits. We will also learn about the modern periodic law, groups and periods, periodic trends - valence electrons, valency, atomic size, metallic, nonmetallic, electropositive, and electronegative characters.