1. Electron Configurations Today we are going to assign addresses to each electron. The energy diagram shows where we put the electrons in every atom BUT there are rules to putting in electrons

2. Labeling of Electrons Electrons in atoms are arranged in the following order: LEVELS SUBLEVELS (shape/type) ORBITALS (which specific orbital)

3. Rearrange The Periodic Table

4. Time to Color:

5. Labeling: 2s 3s 4s 5s 6s 7s 1s 2p 3p 4p 5p 6p 3d 4d 5d 6d 4f 5f

7. s orbitals d orbitals Number of orbitals Number of electrons 1 35 2 610 p orbitals f orbitals 7 14 How many electrons? Find each orbital type on your energy diagram and fill in the table below:

8. LithiumLithium Atomic number = 3 (Total of 3 electrons) Starting at the bottom is the Aufbau principle Electrons are represented with arrows, but no two can be exactly the same. Therefore one has a spin up, and one has a spin down, just to differentiate between them This is the Pauli Exclusion Principle

9. CarbonCarbon Atomic number = 6 (Total of 6 electrons) (Total of 6 electrons) HUND’S RULE : When placing electrons in a set of orbitals having the same energy, we place them singly as long as possible.

10. Can you fill in the energy diagram for the following atoms Al Ca Mn

11. Box Diagrams

12. Practice Box Diagrams N Ne B

13. Electron Configurations 2p 2 Energy Level Sublevel Number of electrons in the orbital 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 6 6s 2 4f 14 … etc.

14. Electron Configurations A list of all the electrons in an atom (or ion): Must go in order (Aufbau principle) 2 electrons per orbital, maximum We need electron configurations so that we can determine the number valence electrons. –The number of valence electrons determines how many and what this atom (or ion) can bond to in order to make a molecule 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 6 6s 2 4f 14 … etc.

15. Let’s Try It! Write the electron configuration for the following elements: H Li N Ne K Zn Pb

16. Shorthand Write the electron configuration for Erbium: 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 6 6s 2 4f 12 Replace With The last filled Noble Gas. In this case, Xenon 6s 2 4f 12 [Xe] 6s 2 4f 12

17. Write Shorthand: Ca Sb W Mo Os Ra

18. Ion Configurations To form anions from elements, add 1 or more e- from the highest sublevel. So, Phosphorus: [Ne] 3s 2 3p 3 + 2e- will become P 2- [Ne] 3s 2 3p 5

19. Ion Electron Configuration S 2- Mg 2+