Class 11 Chemistry Chapter 2 Structure of Atom – Revision Notes

Quick revision notes for Class 11 Chemistry Chapter 2 (Structure of Atom). These Class 11 Chemistry Chapter 2 notes are ideal for quick revision just before exams.

Subatomic Particles & Models

• Electron (Thomson), Proton, Neutron (Chadwick).
• Thomson → Rutherford → Bohr → Quantum mechanical model.

Quantum Numbers

• n (shell), l (subshell), m_l (orientation), m_s (spin).

Filling Rules

• Aufbau: lowest energy first.
• Pauli: no two electrons share all 4 quantum numbers.
• Hund’s rule: singly occupy before pairing.

Dual Nature

• de Broglie: λ=h/mv.
• Heisenberg: Δx·Δp≥h/4π.

One-Line Summary

Atomic structure evolved from simple particle models to the quantum mechanical model, where electrons are described by probability distributions (orbitals) governed by four quantum numbers and specific filling rules.

Written by Satish

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