Creating a Positive Learning Environment for Everyone Be respectful of your classmates Save conversation for clicker portions of lecture Put cell phones in “airplane” mode Turn off tablets Close laptops

Announcements Exam #3: Thursday, Dec. 7th, 7:00-8:30pm (Conflict: 5:00-6:30pm, sign up in 1026 Chem Annex) No calculators allowed Conflicts to conflicts? Must TELL me by TOMORROW! Q & A Review Sessions will be posted soon Activity 3: Making Models of Molecules lab write-up due tomorrow in discussion Lon-capa HW Remaining Homework 7 – Type 1 due Monday, 12/4 by 7pm Homework 8 – Type 1 due Wednesday, 12/6 by 7pm Review Questions for Exam III due Wed, 12/6 by 10pm Prelecture Assignments

Overall goal: Atomic Structure Chemical Bonding 3D Molecular Structure Molecular Properties

Clicker #1 Which of the following Lewis structures is correct for CO2 (following the octet rule)? A) B) C) D) All of the structures are correct and are considered to be resonance structures. E) Only two (a and c) of the structures are correct.

Clicker #2 Which of the following supports why Lewis structures are not a completely accurate way to draw molecules? A) The Lewis structure for O2 shows all electrons as paired but when liquid O2 is poured onto a magnet, it behaves as a molecule with an unpaired electron. B) There are sometimes multiple valid Lewis structures for a single chemical species. C) When adding up the number of valence electrons for a molecule (such as nitrogen monoxide), it is possible to get an odd number which would make it impossible to satisfy the octet rule for all atoms. D) All of the above statements support why Lewis structures are not a completely accurate way to draw molecules. E) Lewis structures are the most accurate way to draw molecules and are completely correct.

Overall goal: Atomic Structure Chemical Bonding 3D Molecular Structure Molecular Properties

BF3 SO2 CCl4 NF3

Clicker #3 Does CCl4 have an overall net dipole moment (is it polar overall)? A) Yes, the electrons are found more towards chlorine. B) Yes, the electrons are found more towards the carbon. C) No, the electron distribution is symmetrical around the central atom.

SF4

Clicker #4 Does H2O have an overall net dipole moment (is it polar overall)? A) Yes, the electrons are found more towards oxygen. B) Yes, the electrons are found more towards the hydrogens. C) No, the electron distribution is symmetrical around the central atom.

Clicker #5 Does PCl5 have an overall net dipole moment (is it polar overall)? A) Yes, the electrons are found more towards phosphorus. B) Yes, the electrons are found more towards the chlorines. C) No, the electron distribution is symmetrical around the central atom.

Clicker #6 Does IBr2– have an overall net dipole moment (is it polar overall)? A) Yes, the electrons are found more towards the central iodine atom. B) Yes, the electrons are found more towards the outer bromine atoms. C) No, the electron distribution is symmetrical around the central atom.

Clicker #7 Does XeCl4 have an overall net dipole moment (is it polar overall)? A) Yes, the electrons are found more towards xenon. B) Yes, the electrons are found more towards the chlorines. C) No, the electron distribution is symmetrical around the central atom.