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Unit 8: Kinetics and Equilibrium

Unit 8 of our 9-unit course focuses on the topics of Kinetics and Equilibrium.  We will explore details about reaction rates, considering what variables affect the rates of reactions and why, how reactions take place, and how experimental data can be used to determine equations that describe reaction rates. This is the topic of Kinetics. But we will also explore the topic of Equilibrium. This includes topics like reversible reaction systems in which reactants don't completely  react away and what can be done to persuade them to more fully react. We will use equilibrium equations to predict the final concentrations and/or pressures of reactants and products. The unit will end with a return to the topic of acids and bases at which time we will use our completed and refined titration system to conduct our student-designed lab investigation ... just in time for the May 24 Maker Fair.

The unit will include the usual blend of conceptual knowledge with mathematical analysis. There will be approximately 9 days devoted to the unit with the first 2-3 days being focused on the topic of Kinetics.



Second Semester Integrated Project

The second semester integrated project is the creation of an automated titrating system that titrates a sample of acid using NaOH. You will use an Arduino to control the amount of volume added to the titrant. You will also control the stirring and monitor the pH for changes. A sudden and dramatic pH change is a signal that the endpoint has been reached.


"Science Fair" Project

Each engineering project group will be responsible for using their engineered titration system to conduct a student-designed science experiment. This science experiment will be designed over the next two weeks (4/24  til May 5) and conducted during the weeks of May 9 to May 19.

As would/should occur in any engineering/science situation, the process will be INCREMENTAL. Do not expect LAST MINUTE SURGES. Last minute surges will not be possible on this project. Put another way, there is no single due date.

Currently, this is the step that each project group must accomplish: By Thursday, submit two testable questions to the teacher that your group would be interested in answering using your titration system.


What is Meant by "Annotating" in a Lab Report

We tend to do two types of labs - (1) labs that include multiple observations in an effort to identify properties and trends in those properties and (2) labs that include careful measurements and subsequent calculations in an effort to determine an unknown quantitative value. When doing the second of these two types of labs, there are several measurements followed by an extensive set of calculations. The Conclusion section is generally short but the Calculation section is long. The role of the Calculations is to document and present the logic as to how the measurements lead to the quantitative value that the lab proposes to find. A good presentation of measured data and calculations will include annotations. Annotations are short notes that convey what the subsequent calculation involves and the logic behind it. The concept of an annotation was discussed in class on Tuesday, December 6. For those who would like to review the discussion, the notes are provided here.

View Notes on Annotations.



Mr. H's Little Secret

Pssss.  Hey bud! I have a secret to share. Now that you know how to calculate the molar mass, here's a little cheat you should be permitted to use. It's called the Molar Mass Calculator and you will find it by following the links. You type in the formula and it calculates the molar mass. (Revised links on 2/28/17)

Molar Mass Calculator ... 2 decimal places

Chemical Molar Mass Calculators ... several decimal places ... a bit buggy?






    Online Homework

WebAssign


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Today in Class

>> Tuesday, April 25 <<

Focus Question(s):
  • How can concentration-time data be used to determine a rate law equation?
  • What variables affect the rate of reaction?
  • What is a reaction mechanism and how can potential mechanisms be evaluate in light of a rate law equation?

Activities:
  • Seating Charts, Test Comments, Science Fair Project
  • Reaction Rates: Concentration vs. Time; rate defintion; rate law equations; method of initial rates; Packet, pp. 4-6, Q#4, 5, 6
  • Lab KE1 - Reaction Rates
  • Chapter 17.1-2 Reading Guide (pp. 1-2)
  • Introduction to Reaction Mechanisms (p. 7, Q#1)


Homework:   
  • WebAssign: Reaction Rates
  • WebAssign: Chapter 17:3-4 Reading Guide
  • ID two Testable Questions



Help:

  • Coming Soon






Next Time in Class

>> Thursday, April 27 <<

We will continue to discuss reaction rates and reaction mechanisms. We will make the connection to the topic of equilibrium using Lab KE3. We will discuss the Reading Guide (pp. 11-12) and the concept of equilibrium position (p. 13)





Periodic Tables

Are you in need of a periodic table?  Try one of the following websites:






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