Class Blog 12/12/13

Beginning of Class:

Checked in 2 homework assignments:

o   The 3^rd sheet of Electron Configurations and Orbital Diagrams

o   Quantum Numbers WS #2

Notes:

Valence Electrons:

What do you notice about the e- configs for ions?

-They are the same as the e- configs for Noble Gases

 Valence: The number of electrons in the highest occupied energy level (n)

Example:

Na (11e-): 1s­­­²2s²2p⁶3s¹

·       Highest energy level is 3, so the valence would be 1 for all elements in group 1

The Octet Rule: A valence of 8 is the most stable. Elements lose or gain electrons to achieve a Noble Gas configuration

Abbreviated Configurations:

Ex: Bromine (Neutral).

            35e-s

            1s²2s²2p⁶3s²3p⁶4s²3d¹⁰4p⁵

            *The bold part is the Argon configuration, so…

[Ar]4s²3d¹⁰4p⁵

                How do you do this?

*Back up to the last noble gas, put it in brackets, and continue the rest of the config

 More Examples:

·       Na: [Ne]3s¹

·       Ca: [Ar]4s²

Excited State Configurations:

1s²2s²2p⁵3s¹

-        Notice that 2p is not filled 

1s²2s²2p⁶  ----> This is what the ground state would be. An electron jumped up = Excited State.

We also filled out this periodic table in class today to help us write the electron configuration of elements.

Homework:

• The fourth page of the "Electron Configurations and Orbital Diagrams" worksheet 
• The “Shells, Subshells, and Orbitals” worksheet
•   Study for the quiz tomorrow. It will cover everything we have learned so far and it is NOT a partner quiz. People who will not be at class tomorrow because of Snowball will have to make up the quiz on Monday.