Pedagogy of Physical Science - Part II (Atomic Structure), IX Std Science, Physical Science, B.Ed Pedagogy, II B.Ed Physical Science, Atomic Structure, IX samacheer science, Pedagogy, Discovery of Nucleus, Rutherford's Atomic model, Limitations in Rutherford's model, Bohr's model of an atom, Limitations of Bohr's model, Discovery of Neutrons, Properties of Neutrons, Characteristics of fundamental particles, Orbits, Nucleus, Atomic number and Mass number, Electronic configuration of atoms, Geometric representation of atomic structure of elements, valence electrons, metals, valency, Isotopes, Isobars and Isotones, Laws of chemical combination, laws of multiple proportions, Law of reciprocal proportions, gay lussac's law of combining volumes, quantum numbers,