Modern periodic law and Periodic table
PERIODIC TABLE · Why do elements are to be classified? · It is very difficult to study the chemistry of each and every element · Classification of elements enables a better under standing of elements and their properties. · The fundamental properties which govern them. · Properties of elements repeat periodically like seasons in the nature · Atomic number or Electronic configuration is basis for the periodic arrangement of the elements MENDELEEV’S PERIODIC TABLE · In 1861 Mendeleev for the first time arranged the elements in the increasing of order of their atomic weights in the form of a table · He divided the elements into groups (vertical columns) and periods (horizontal rows) MODERN PERIODIC LAW · Mosely (1911) proposed the long form of periodic table · The physical and chemical properties of elements are periodic functions of their Atomic Numbers or electronic configurations. MODERN PERIODIC TABLE · It is based on