Structure of the Atom is one of the most interesting chapters of Class 9 Science as it explains the discovery of subatomic particles and various atomic models. To make revision easier, we are providing Class 9 Science Chapter 4 Handwritten Notes PDF (Free Download) as per the latest NCERT syllabus 2025-26.
📘 About the Notes
These handwritten notes are prepared in a simple and easy-to-understand format. They include theories, diagrams, and key points to help students revise quickly. Perfect for last-minute exam preparation.
📚 Key Topics in Chapter 4 – Structure of the Atom
- Discovery of Subatomic Particles – Electron, Proton, Neutron.
- Thomson’s Model of the Atom – Plum pudding model.
- Rutherford’s Model of the Atom – Alpha particle scattering experiment and nuclear model.
- Bohr’s Model of the Atom – Postulates and energy levels.
- Neutrons – Discovery and importance.
- Distribution of Electrons – The 2n² rule.
- Valency – Definition and examples.
- Atomic Number and Mass Number.
- Isotopes, Isobars, and Isotones – Definitions and differences.
- Applications of Isotopes.
📥 Download Class 9 Chapter 4 Notes PDF
These handwritten notes are fully aligned with the NCERT Class 9 Science syllabus 2025-26. They cover all important definitions, models, and diagrams to ensure strong exam preparation.
📥 Download Structure of the Atom Notes PDF
✅ How to Study This Chapter Effectively
- Learn the atomic models and their limitations in sequence.
- Revise electron distribution and practice questions based on the 2n² rule.
- Understand the concept of valency with examples from the periodic table.
- Memorize the differences between isotopes, isobars, and isotones.
- Use diagrams for Rutherford’s experiment and Bohr’s model.
🎯 Why Use These Notes?
- Prepared according to the latest NCERT syllabus 2025-26.
- Neat handwritten notes with diagrams and examples.
- Covers all atomic models and key definitions.
- Best for CBSE exams, NTSE, and Olympiad preparation.
🔑 Conclusion
Structure of the Atom is a chapter that builds the base for higher-level Chemistry. With these Class 9 Science Chapter 4 Handwritten Notes PDF, students can revise all concepts quickly and boost their exam preparation for the 2025-26 CBSE board exams. Download the notes now and study smart.
