Cornell Notes: Please take out your notebook and properly set up your paper. Topic: Electron Configuration Date: 11/28/2012

Electron Configuration: Standard Notation & Noble Gas Configuration Mapping the electrons

Objective: SWBAT apply the Pauli exclusion principle, the aufbau principle, & Hund’s rule to write electron configuration notation. Essential Question: Predict the complete electron configuration and Noble Gas Configuration of Sulfur.

What is an Electron Configuration? a shorthand description of how electrons are arranged around the nucleus of an atom.

Why is electron configuration important? It helps us predict chemical behavior.  We can predict whether two elements will react or not; and if they react, we can also predict what kind of reaction we are likely to have, as well as how strong the reaction will be.

Standard notation is like giving the address of an element based on it’s electron configuration… The periodic table contains four blocks: s, p, d, and f. Each period (row) of the PT has an energy level (like floors in a building). In standard notation, always begin at the starting point of hydrogen, and snake through each period from left to right until the element is reached.

Take out your blank periodic table and outline the four “blocks”: s, p, d, & f. *If you have highlighters or colored pencils, use them now! DO NOT write inside the boxes!!

Energy Levels on the Periodic Table  for the S & P block, the energy level (n) = the period number  for the D block, the energy level (n) = the period – 1  for the F block, the energy level (n) = the period – f 4f 4d 1s 2p 3p 3d 2s Period Numbers

Blocks in the Periodic Table

Energy Levels on the Periodic Table s s 1 2s 2 2p 1 1s 2 2p 2 5f 1 4f 1 4d 2 4d 1 3d 3 3d 2 3d 1 3p 2 3p 1 5f 2 4f 2  for the S & P block, the energy level (n) = the period number  for the D block, the energy level (n) = the period – 1  for the F block, the energy level (n) = the period – 2

Electron Configuration Notation Table

What is the standard notation of Fluorine? F: 1s 2.. F

What is the standard notation of Fluorine? F: 1s 2 2s 2.. F

What is the standard notation of Fluorine? F: 1s 2 2s 2 2p 5 F

Standard Notation of Fluorine Main Energy Level Numbers 1, 2, 2 Sublevels Number of electrons in the sub level 2,2,5 1s 2 2s 2 2p 5

Practice creating the standard notation for: N: Mg Br Tc

What is the standard notation of Nitrogen? N: 1s 2.. N

What is the standard notation of Nitrogen? N: 1s 2 2s 2.. N

What is the standard notation of Nitrogen? N: 1s 2 2s 2 2p 3 N

Practice creating the standard notation for: N: 1s 2 2s 2 2p 3 Mg Br Tc

Practice creating the standard notation for: N: 1s 2 2s 2 2p 3 Mg: 1s 2 2s 2 2p 6 3s 2 Br Tc

Practice creating the standard notation for: N: 1s 2 2s 2 2p 3 Mg: 1s 2 2s 2 2p 6 3s 2 Br: 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 5 Tc

Practice creating the standard notation for: N: 1s 2 2s 2 2p 3 Mg: 1s 2 2s 2 2p 6 3s 2 Br: 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 5 Tc: 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 5

Shorthand Notation (“Noble Gas Configuration – NGC”) Use the last noble gas that is located in the periodic table right before the element. Write the symbol of the noble gas in brackets. Write the remaining configuration after the brackets. Ex: Fluorine: [He] 2s 2 2p 5

Practice creating the Noble Gas Configuration (NGC) for: N: Mg: Br: Tc:

Practice creating the Noble Gas Configuration (NGC) for: N: [He] 2s 2 2p 3 Mg: Br: Tc:

Practice creating the Noble Gas Configuration (NGC) for: N: [He] 2s 2 2p 3 Mg: [Ne] 3s 2 Br: Tc:

Practice creating the Noble Gas Configuration (NGC) for: N: [He] 2s 2 2p 3 Mg: [Ne] 3s 2 Br: [Ar] 4s 2 3d 10 4p 5 Tc:

Practice creating the Noble Gas Configuration (NGC) for: N: [He] 2s 2 2p 3 Mg: [Ne] 3s 2 Br: [Ar] 4s 2 3d 10 4p 5 Tc: [Kr] 5s 2 4d 5

End of Notes! Now it is time to: 1. Summarize your CN 2. Answer the essential question.