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CHEM102: General Chemistry II

Unit 1: Rates of Reaction   As you learned last semester, Gibbs free energy will tell us whether a reaction will occur spontaneously.  It won’t, however, tell us how long the reaction will take from start to finish.  In this first unit, we will learn the factors that determine the speed of a reaction.  We will also learn about rate constants and how they affect speed.  Finally, we will learn how to use experimental rates to figure out rate law and rate order, which together link the rate constant to the concentration of reactants to determine speed.

1.1 Collision Theory   - Reading: Boundless: “The Collision Theory” Link: Boundless: “The Collision Theory” (PDF)

 Instructions: Read this article, which quantitatively explains how
chemical reactions occur and why each reaction proceeds at a
different rate. For additional support, you may visit the original
Boundless page which contains supplementary flashcards, a study
guide, and a quiz.  

 Terms of Use: This resource is licensed under a [Creative Commons
Attribution-ShareAlike 3.0 Unported
License](http://creativecommons.org/licenses/by-sa/3.0/). It is
attributed to Boundless, and the original version can be
found [here](https://www.boundless.com/chemistry/chemical-kinetics/activation-energy-and-temperature-dependence/collision-theory/).

1.2 Five Factors of Rate Reaction   1.2.1 Nature of Reactants   - Reading: Boundless: “Measuring Reaction Rates” Link: Boundless: “Measuring Reaction Rates” (PDF)

 Instructions: Read this article, which explains how reaction rates
are measured.  For additional support, you may visit the original
Boundless page, which contains supplementary flashcards, a study
guide, and a quiz.  

 Terms of Use: This resource is licensed under a [Creative Commons
Attribution-ShareAlike 3.0 Unported
License](http://creativecommons.org/licenses/by-sa/3.0/).  It is
attributed to Boundless, and the original version can be found
[here](https://www.boundless.com/chemistry/chemical-kinetics/reaction-rates/measuring-reaction-rates/).

1.2.2 Concentration   - Reading: Boundless: “Influences on Reaction Rate” Link: Boundless: “Influences on Reaction Rate” (PDF)

 Instructions: Read this article, which explains how reaction rates
are influenced by changing concentration, pressure, or temperature.
 You will also learn how reaction rates are influenced by the
absense or presence of a catalyst.  For additional support, you may
visit the original Boundless page, which contains supplementary
flashcards, a study guide, and a quiz.  This resource also covers
sub-subunits 1.2.3 and 1.2.4.  

 Terms of Use: This resource is licensed under a [Creative Commons
Attribution-ShareAlike 3.0 Unported
License](http://creativecommons.org/licenses/by-sa/3.0/).  It is
attributed to Boundless, and the original version can be found
[here](https://www.boundless.com/chemistry/chemical-kinetics/reaction-rates/influences-on-reaction-rate/).

1.2.3 Temperature   Note: This topic is covered by the reading assigned below sub-subunit 1.2.2.

1.2.4 Catalyst and Activation Energy   Note: This topic is covered by the reading assigned below sub-subunit 1.2.2.  While all catalysts increase the reaction rate, it is important to note that some catalysts are actually consumed over the course of a reaction, though they are in the end produced again (along with the products).  Because catalysts therefore appear in both the reactants and the products, we remove them from the final balanced equation.  This may give you the impression that they do not participate in the reaction—but they actually do.  Keep this concept in mind as you take a look at equations!

1.3 Rate Law   1.3.1 Determining Reaction Rates   - Reading: Purdue University Chemistry: William R. Robinson’s notes on Determining Reaction Rates Link: Purdue University Chemistry: William R. Robinson’s notes on Determining Reaction Rates (HTML)
 
Instructions: Please read this section to gain a general understanding of how to mathematically calculate chemical rates.

 Terms of Use: Please respect the copyright and terms of use
displayed on the webpage above.

1.3.2 Rate Law and Order of a Reaction   - Reading: Purdue University Chemistry: William R. Robinson’s notes on Reaction Order Link: Purdue University Chemistry: William R. Robinson’s notes on Reaction Order (HTML)
 
Instructions: Please read this section beginning with the title Rate Laws and Order of a Reactionto gain a general understanding of the concept of reaction order.  

 Terms of Use: Please respect the copyright and terms of use
displayed on the webpage above.

1.4 Reaction Mechanisms   Note: Though every reaction contains fast and slow steps (parts), keep in mind that only the slow step(s) determines the rate.  If you have more than one slow step, add them together to obtain the rate law.  Sometimes the rate law will not include all reactants. The reactants that are not included in the rate law are zero-order!

  • Reading: University of California, Davis: ChemWiki: “Reaction Mechanisms” Link: University of California, Davis: ChemWiki: “Reaction Mechanisms” (PDF)

    Instructions: Read this article, which explains the dynamics – more specifically, the kinetics – of a reaction.  You will examine reaction mechanisms at the step-by-step level to learn about the properties of the overall reaction.  Please be sure to work through the problems at the end of the article at check your answers against the solutions.
     
    Terms of Use: This resource is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.  It is attributed to the University of California, Davis, and the original version can be found here.

1.5 Experimental Rate Law   - Reading: Purdue University Chemistry: William R. Robinson’s notes on Experimental Rate Law Link: Purdue University Chemistry: William R. Robinson’s notes on Reaction Experimental Rate Law (HTML)

 Instructions: Please read this section beginning with the title
*Rate Laws from Rate Versus Concentration Data*to gain a general
understanding of determining reaction rate and order when provided
with experimental data.  This section provides several examples to
illustrate these concepts.    

 Terms of Use: Please respect the copyright and terms of use
displayed on the webpage above.
  • Reading: Purdue University Chemistry: William R. Robinson’s notes on Integrated Rate Law Link: Purdue University Chemistry: William R. Robinson’s notes on Reaction Integrated Rate Law (HTML)

    Note: In order to calculate rate law from experimental data, use your deductive reasoning.  Once you have looked at the data and isolated one reactant while keeping the others the same, see how changes in the concentration of that single reactant affect rate law.  You will quickly yield the rate law for that reactant (keep in mind that you may have a zero-order reactant).  

    Instructions: Please read this section beginning to gain a general understanding of how to determine reaction rates when graphs of concentration versus time are provided.  Please note that concentration is on the y-axis and time is on the x-axis.  

    Terms of Use: Please respect the copyright and terms of use displayed on the webpage above.