Week of Nov 30

Monday: Today we started the equilibrium unit with my oscillating rxn demo that didn’t work probably b/c I did not use distilled water! Ugh! Then we did the reversible reactions simulation from PhEt and then did the penny moving lab to derive the equilibrium constant and learn the difference between the constant and the equilibrium position as well as factors that affect both of those.  In the last 15 minutes I went through some of the notes I’ve given you including the graphs and how to write equilibrium constants from reactions + the meaning of the equilibrium constant.


Week of Nov 16th

Monday: Dye fading lab! Note to self: blue needs full strength bleach and takes only about 5 min. Red works the best with the weaker bleach. Yellow does not work. Also, we need more colorimeters!

Tuesday: Do Dye Fading Lab Analysis

Wedneseday: We started with the ozone article and questions after you guys got your labs turned in.  This was good b/c it let you practice reaction mechanism stuff. We briefly reviewed a couple of concepts like intermediate v catalyst  v. activated complex/transition state and which step in a mechanism is the slowest (highest activated complex).  Then I started my lecture on the Arrhenius equation but we didn’t get very far before class was over.  Basically gave you the equations but didn’t do any problems…

Thursday: Today we finished up the  activation energy concepts and went over some half life stuff that can also be tricky (know %’s).  Then I handed out the review guides and the dye fading labs so you can spend tomorrow reviewing for your test on Monday.  Here’s the notes and what not from yesterday and today.  List of topics for test:

  • Check detailed list on unit outline.
  • Boltzmann distribution
  • Effusion/Diffusion
  • Collision theory & 4 factors that affect rxn rates. Incorporate Boltzmann in to discussion for Temp and Catalysts
  • Potential energy diagrams that show affect of catalyst. Identify number of steps, contrast activated complex w/ intermediate.
  • Rate laws
    • Differential: using does rate double when concentration doubles?
    • Integrated: plot graphs of concentration v. time and determine which is most linear.
      •  Use linear equation to solve for conc at certain times,
      • half lives,
        • find half life from graph of concentration of reactant v. time and deterimine if first or 2nd order.
    • Reaction mechanisms – use mechanism to determine rate law, molecularity, identify mechanisms that don’t fit rate laws.
  • Activation energy (arrhenius equation)
  • Apply above to ozone layer depletion and catalytic convertor.

Friday: no class. I am at a conference. study for your kinetics test on Monday (here’s the answer key to the review guide that says IB HL at the top)

Week of Nov 9

Monday: Today we did chemactivity 36 to learn how to calculate reaction rates.  I tried to do the iodine clock demo, but it did not work for some reason…next we tried the iodine clock lab but had major difficulties with it. Some of you got no results and some of you had the middle concentrations change color the fastest.  Weird. Will have to make new stuff.

Homework: continue with readings on catalytic convertor/air pollution and effusion/diffusion.

Tuesday: Today we learned how to determine the rate law and read reaction rate graphs.  Homework is to finish pages 13 to 15 in packet.

Wednesday: Grading day, no school.

Thursday: Today we started with a review of determining rate law.  So many of you professed having major difficulty with the homework that I gave some time to explain some of the harder problems. Boo!  I also went over our first integrated rate law (just first order). Here’s the notes.  

Homework is to watch the reaction mechanisms video being careful to watch for these items.  Also continue to work on packets and textbook problems listed on unit outline (rubric).

Week of Nov 2

Monday: Design lab time! Last day to collect all your data.  Grades as follows: Due next Monday, Nov 9th.

Experimental Methods Math Data Collection and Presentation
 Shows thorough understanding of method, thorough explanation of a detailed plan (procedures, including calculations) as we as thorough evaluation of results.  Demonstrates thorough ability to apply mathematical process and can justify their use (this time, use gas laws). (clearly labeled calculations w/ any assumptions stated, inc. Just and application of s.f. Rules)  Thorough measurement technique, presents data clearly and correctly.
 Less thorough, but competent Demonstrates ability to apply mathematical routines and can sometimes justify their use. Less thorough. (s.f., labeling)
 Lacks justification  Demonstrates ability to apply mathematical processes to solving chemistry problems. Poor technique. (miss. Est. dig, +/-)
Discussion or plan is weak or missing too much. Demonstrates some ability to apply mathematical processes to solving chemistry problems Missing essential information
 No Evidence  No Evidence  No Evidence

So for Methods/Error Analysis make sure you:

  • Calculations
    • Show work/ justify with words as you go along like you did on mixtures lab
    • Justify number of sig figs in final molar mass.
    • Calculate percent error.
      • Sample 1 was Na
      • Sample 2 and 3 were K
  •  Procedures
    •    Say what you are doing (steps),
    •    why you are doing it that way (rationale for choices – use KMT principles),
    •    how you will get an answer (calculation), including plan for certain sig figs
  • Error Analysis/Conclusion
    •  Did you get good R values? Was one gas better than the other? Are they similar? Why should they be similar?
    • Limitations of method/equipment/conclusions,
    • discussion of variability (precision…number of decimal places since you don’t have multiple trials) and accuracy (percent error) of the data that is justified
      • State the error
      • Determine whether it was random or systematic and justify this
      • What effect did the error have on the results – in detail. Do math if necessary. Do not just say it would throw off the result. Give an example.

Tuesday: No school, teacher professional day (also voting day)

Wednesday: Test

Thursday: Simulation on Rxn Rates.  HW: Work on lab

Friday: Boltzmann notes and worksheet + catalyst demos, potential energy diagrams and explanations of Temp and Ea using Boltzmann. HW: effusion/diffusion reading and questions and catalytic converter article.