BCHEM 142A   General Chemistry I

Winter 2013                  General Assignment #9              March 2 , 2013

Reading Assignments and prep work for class in week 9 (March 3 – 9):

• For Tuesday, Mar 5

• Thoroughly review sections 6.4 – 6.8 of Zumdahl..
• Be prepared to complete the Hanson 15-4 problems in class.
• Read and thoroughly study sections 7.1 – 7.4 of Zumdahl.
• Read Hanson Activity 16-1 and complete Key Questions 1-9 on pages 288-89 before class.
• These Key Questions will be the subject of a clicker quiz during class on Tuesday

• For Thursday, Mar 7
• Read and thoroughly study sections 7.5 – 7.7 of Zumdahl.
• Read Hanson Activity 16-2. Note that you will not encounter the free energy concept until Chapter 10. Only some parts of this activity will be used in class. See the comments at bottom of this page.
• Complete Key Questions 1 and 3 (skip 2) on p.293 and 4 and 5 p.296 before class. Ignore the discussion of “Resonance” at this time.
• These Key Questions will be the subject of a clicker quiz at the start of class on Thursday.

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Note: The concept of free energy change ΔG is used in Hanson 16-2, but has not been introduced up to this point in Zumdahl. One way to think of it is that free energy decreases for spontaneous reactions and increases for reactions that do not proceed spontaneously. Further, large decreases in free energy (ΔG negative and large) are characteristic of reactions that proceed far to the right to equilibrium. Large increases in free energy (ΔG positive and large) are characteristic of reactions that are shifted far to the left at equilibrium. Obviously this concept is related to equilibrium constants, and the author provides such a relationship between K and ΔG. We will not use that equation at this point, other than to recognize it as embodying the semi quantitative concepts presented here.

Finally the author applies the ”p” operator to equilibrium constants such as K_a. It has the same meaning as in pH: pK_a ≡ -log(K_a)

After Classes:  Always complete the exercises and problems for the active learning exercise(s) if you did not get them finished in class.  It is important to complete these as they may be checked during the term.

Homework : See OWL for details and due dates. The summary of assignments is:

· Required Assignments due Mar 11, 11:00 AM: sections of chapter 6

· Required Assignments due Mar 18, 11:00 AM: sections of chapters 7 and 8

· Extra Credit due March 19, 11 AM: 6-EOC

· Extra Credit due March 19, 11 AM: 7-EOC and 8-EOC