1. Electron Configuration Chemistry Mrs. Coyle

2. Electron Configuration The way electrons are arranged around the nucleus.

3. Three rules are used to build the electron configuration: Aufbau principle Pauli Exclusion Principle Hund’s Rule

4. Aufbau Principle Electrons occupy orbitals of lower energy first.

5. Pauli Exclusion Principle An orbital can hold only two electrons and they must have opposite spin.

6. Hund’s Rule In a set of orbitals, the electrons will fill the orbitals in a way that would give the maximum number of parallel spins. Analogy: Students could fill each seat of a school bus, one person at a time, before doubling up.

7. Aufbau Diagram for Hydrogen

8. Aufbau Diagram for Helium

9. Aufbau Diagram for Lithium

10. Aufbau Diagram for Beryllium

11. Aufbau Diagram for Boron

12. Aufbau Diagram for Carbon

13. Aufbau Diagram for Nitrogen

14. Aufbau Diagram

15. Blocks in the Periodic Table