1. Lesson 15: Duality and the Wave Mechanical Model

2. Review Thomson discovers that el- are – particles in atoms
So we can NOT say where an el- actually is
This is Heisenberg’s Uncertainty Principle
We can only state the probability of finding an el- in a given region of space around the nucleus---this space is called an ORBITAL

3. El- are weird! El- are - particles in the atom
El- also seem to act as waves
Double Slit expmt

4. Waves create an interference pattern.

5. Particles do NOT create interference.

6. El- create an interference pattern, so sometimes el- do act like waves.

7. Duality Theory De Broglie El- seem to act as WAVES or PARTICLES
Maybe all MATTER can act as a wave or a particle.

9. Modern Wave-Mechanical Model
Atoms have a positive nucleus with protons and neutrons inside, and the nucleus is surrounded by vibrating el- clouds
El- can be thought of as waves or particles
El- do not follow rules of classic physics
El- occupy certain high prob. areas of the nucleus called orbitals