Filling Electron Orbitals

1. Filling Electron Orbitals • Orbitals are the area in space where electrons are found • Each individual orbital holds 2 electrons • There are four main shapes which hold a different number of electrons

2. Shapes of Orbitals • The four shapes are s, p, d, and f

3. Shapes of the Orbitals • Each shape holds a different number of orbitals • s has 1 orbital, p has 3 orbitals, and d has 5 orbitals • www.ptable.com

5. Energy Levels • Each period is a new energy level • Like an elevator, electrons cannot exist between energy levels!

6. General Rules • Aufbau Principle – Electrons fill lowest energy level first • Analogy: Lazy Tenant Rule

7. General Rules • Pauli Exclusion Principle – Electrons must have opposite spin (up/down) when in the same orbital • Analogy: Yin and Yang Rule

8. General Rules • Hund’s Rule – Electrons in equal energy orbits fill orbitals with parallel spin • Analogy: Empty Bus Seat Rule

10. Orbital Notation • Specific order for filling electrons – based on periodic table • Examples • Beryllium • Oxygen

11. Orbital Notation • Examples • O2- • Titanium

12. Electron Configuration • Examples • Silicon • Selenium • Manganese

13. Shorthand Electron Config • Shorter version of writing electron configurations • Noble Gas Core – inner core of electrons not involved in chemical bonding