8. Journey Inside the Atom - Notes & Summary | Class 9 Science Exploration

In this video we will study Notes and Summary of Chapter 8 - "Journey Inside the Atom" taken from Class 9 / Grade Science NCERT Textbook - Exploration. Chapters: 00:15 - Introduction 01:24 - Rediscovering the Roots of Atomic Theory 02:19 - Dalton’s Atomic Theory 02:54 - A Short Historical Journey Through Atomic Models 03:18 - Thomson’s Model of an Atom 04:52 - Testing Thomson’s Model: The Gold Foil Experiment 05:59 - Rutherford’s Model of an Atom 07:10 - Limitations of Rutherford’s Model 07:49 - Discovery of the Proton 08:32 - Bohr’s Model of the Atom 10:28 - What Components Contribute to the Mass of an Atom? 10:59 - Discovery of the Neutron 11:20 - Subatomic Particles 12:00 - Symbols of Elements 13:23 - Names of some common elements and their symbols 14:20 - Atomic Number 15:49 - Mass Number 17:29 - How Are Electrons Distributed in Different Energy Levels? 20:54 - Combining Capacity of an Atom: Valency 21:49 - Valency 24:02 - Valency of First 18 Elements 25:03 - Isotopes 27:33 - Average Atomic Mass 28:41 - Isobars 29:20 - Difference Between Isotopes and Isobars 30:07 - Important Formulae 31:00 - Important Terms 32:02 - Chapter Summary: At a Glance 33:49 - Quick Revision Points Thank You for watching. #class9 #science #exploration #ncerthinditutor #notes #summary #chemistry