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3 Ex exam 3    10/26

We now have an official Exam Procedure page. Check it out and know what to expect on Tuesday.

Coverage for Exam 3: Exam 3 covers all the material that was covered on LE's 15-17 and HW05 and HW06. Most of the exam is over Chapter 4 (Bonding) from the gchem site. This exam is all about ionic bonding, covalent bonding, Lewis dot and line structures, and VSEPR theory. Not all of chapter 4 is on Exam 3 - coverage stops after VSEPR and before VB theory (there is a blue line on the gchem site that shows the stopping point for Exam 3. Remember that the extra practice assignments (7 and 8) on canvas are a good way to prep as well.

Length / Time for Exam 3: You should expect 20 multiple choice questions. The questions will have a range of point values from 4 points to 6 points. Remember that the point values are included with all questions. The exam is given during class time (9:30-10:45, 11-12:15) which is 75 minutes total which includes the handout time.

Nomenclature is still IN You still need to know your polyatomic ions, formulas, charges, etc. Know what is on this gchem data page for polyatomic ions (you don't have to know the "older" names for metal cations)./p>

Main Equations/Formulas for Exam 3

Coulomb's Law (force): \[F \propto {q_1q_2\over r^2} \]

Coulomb's Law (energy): \[E_{\rm p} \propto {q_1q_2\over r} \]

here is a mobile friendly set of

VSEPR Help Pages

note that for exam 3, there will not be any questions about hybridization - that is VB theory and will be on exam 4

Ionic Bonding

cations and anions

Covalent Bonding

non-metal atoms share electron pairs

Learning Outcomes for Bonding

Students will be able too...

  1. Identify metals and non-metals, and predict the types of compounds (ionic/covalent) that will form from different elements.
  2. Distinguish between molecules, ions, and atoms.
  3. Predict the anion or cation that a main-group element is likely to form.
  4. Relate Coulomb’s law to ionic radii, ionic charge, and lattice energy.
  5. Describe the distance dependence of the potential energy of a covalent bond.
  6. Predict and explain relative bond strength and lengths in a compound.
  7. Name and write formulas for covalent compounds.
  8. Interpret line drawings of chemical compounds with implicit hydrogens, carbons, and lone pairs.
  9. Rank the polarity of covalent bonds based on relative electronegativity.
  10. Define dipole moment and identify polar bonds.
  11. Draw the best Lewis structure (including any resonance structures) for a molecule or polyatomic ion.
  12. Apply formal charges to structures and use them to predict the most likely structure.
  13. Recognize and apply exceptions to the octet rule.
  14. Apply the VSEPR model to determine a molecule's electronic and molecular geometry based on its Lewis dot structure.
  15. Assess if a molecule is polar based on polar bonds and its molecular geometry.

Note that not all chapter 4 outcomes are on Exam 3 - only through VSEPR theory. Numbers 16-22 will be on Exam 4.