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Chapter 5: The Modern Atomic Model

The 20th century was filled with accomplishments in scientific understanding. One of the greatest accomplishments was the development of the quantum mechanical model. Chapter 5 traces the discoveries that led to the model and describes the relationship between the electronic structure of atoms and the properties of elements.

Lesson 1: Physics in the Early 20th Century

• Part a: Emission Spectrum of the Elements
• Part b: The Photon
• Part c: Bohr's Quantized Energy Levels
• Part d: Wave-Particle Duality

Lesson 2: The Quantum Mechanical Model

• Part a: Schrodinger's Wave Mechanical Model
• Part b: Orbitals
• Part c: Energy Levels
• Part d: Quantum Numbers

Lesson 3: Electrons

• Part a: Electron Configurations
• Part b: Electrons and the Periodic Table
• Part c: Exceptions to the Rules

Lesson 4: Periodic Trends

• Part a: The Periodic Law Revisited
• Part b: Atomic Size
• Part c: Ionization Energy
• Part d: Electronegativity