Thursday, December 11th, 2014 HW: Finish Agenda Questions EXCEPT 12 and 13 Objective: We will be able to explain the trends in atomic size. Standard: Catalyst: A. Some plants were not present at each site. B. Some seeds were not present at each site. C. The seeds may have been removed from the dishes by animals other than ants. D. The plants may have been eaten by animals other than ants. Classroom expectations: Wear Kenwood ID. Cell phones, music players, and headphones are put away. Food is disposed of or put away. Dressed appropriately. Notebook is out and you are ready for today’s class. Answer: C ***Table of Contents 12/11 Periodic Trends Packet 89

Thursday, December 11th, 2014 HW: Finish Agenda Questions EXCEPT 12 and 13 Objective: We will be able to explain the trends in atomic size. Standard: Catalyst: The force between the clamp and tape The force between the clamp and the paper or plastic wrapping The force between the earth and the wrapping The force between the Earth and the tape Classroom expectations: Wear Kenwood ID. Cell phones, music players, and headphones are put away. Food is disposed of or put away. Dressed appropriately. Notebook is out and you are ready for today’s class. Answer: C ***Table of Contents 12/11 Periodic Trends Packet 83

Announcements No tutoring today Tutoring next week: Monday and Tuesday Test NEXT Wednesday Get notebooks organized

Catalyst/Announcements Review Agenda Problems Finish investigating atomic size Investigate ionization energy

Atomic Size Across a period: Atomic size decreases as coulombic attraction increases because the electrons are MORE attracted to the nucleus due to the increase in the # of protons and are attracted TOWARDS the positive nucleus making the atoms smaller. Chem team!!! I know my explanations are very over-simplified and so if you think of a better way to word these challenge questions PLEASE feel free to edit/change.  I just wanted to include them because students ask these every year in class.

Trends Atomic size decreases Atomic size increases Chem team!!! I know my explanations are very over-simplified and so if you think of a better way to word these challenge questions PLEASE feel free to edit/change.  I just wanted to include them because students ask these every year in class.

What is ionization energy? Ionization energy is the energy required to remove an electron. The harder an electron is to remove the HIGHER the ionization energy.

Ionization energy Down a group: Ionization energy decreases as columbic attraction decreases because the valence electrons are further away from the nucleus making them easier to remove.

Ionization energy Across a period: Ionization energy increases as columbic attraction increases because the increase in the #of protons causes the electrons to have more attraction to the nucleus making them harder to remove.