Chapter 4 • Class 9 Chemistry
Structure of the Atom
Class 9 Chemistry Structure of the Atom: electrons, protons, neutrons, Thomson, Rutherford and Bohr models, electronic configuration, valency and isotopes on Vidaara.
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1
Discovery of Subatomic Particles & Early Atomic Models
Dalton thought the atom was the smallest, indivisible particle of matter. By the end of the nineteenth century, experiments with electricity passing t…
Start this topic → 2Bohr's Model & Electronic Configuration
To fix the stability problem of Rutherford's model, Neils Bohr put forward a new picture of the atom in 1913. Bohr's postulates Electrons revolve arou…
Start this topic → 3Valency, Atomic Number, Mass Number & Isotopes
Once we know how electrons are arranged in shells, we can describe an atom completely using a few key numbers. Valence electrons and valency The elect…
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