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Chapter 6 icon Lesson #5: Chapter 4 - Aqueous Reactions and Solution Stoichiometry, and Chapter 5 - Thermochemistry
Overview | Resources | Experiences | Practice

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Overview graphic Overview: Learn About Chemical Reaction Types, Solution Stoichiometry, Chemical Energy and More

This module has two portions. The first portion (covered in Chapter Four) extends our discovery of solution type from module four and expands to reach solution stoichiometry. The second portion (Chapter 5) examines the role that energy plays in a chemical reaction (and how we can manipulate energy to get desired products).

Chapter 4 continues our discussion on types of reaction. You should be familiar with all five types: precipitation, acid-base, gas-forming, combustion, and oxidation. We will also explore oxidation numbers in order to ascertain if a reaction occurs with a transference of electrons. We will explore the concepts of acids and bases, and we will know how the concept of electrolyte helps us understand if an acid or base is "strong" or "weak". We will also extend our stoichiometry studies from Chapter 4 with a look at solution stoichiometry, especially when applied in a titration.

For a complete list of important concepts in Chapter 4, see the Chapter 4 Study Guide.

Chapter 5 introduces us to enthalpy, DH, one of the thermodynamic properties we will be exploring this year. Generally, if a reaction is exothermic (heat releasing), the reaction will occur naturally; conversely, if a reaction is endothermic (heat absorbing), the reaction will not occur without outside stimulus (i.e. adding heat.) We will use values of enthalpy to calculate enthalpies of reaction using Hess's Law and calorimetry.

For a complete list of important concepts in Chapter 5, see the Chapter 5 Study Guide.

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resources picture Resources: Read Chapter Four and Chapter Five in the Text

For this module you should read Chapter Four and Chapter Five in your textbook.

The following screencasts might prove useful to you as you study these chapters. Note that you must have Quicktime installed to watch these screencasts.

The Chapter Four PowerPoint lecture notes and Chapter Five PowerPoint lecture notes which accompany this lesson will be helpful to you when going through this section. These are Web versions of the PowerPoint notes I use in my "normal" CH 221 class and should let you see what is important to me in this chapter.

A variety of handouts are available from Chapter Four and Five. Feel free to explore all of them or just the ones which give you difficulty.

You might wish to explore these interactive exercises:

These interactive exercises from W.W. Norton and Company (ChemTours) might prove useful as well:

Once you have mastered the concepts listed above, check out the Chapter Four Concept Guide and the Chapter Five Concept Guide for a series of worked problems relating to this module. They will help you to ensure the mastery of the knowledge from this section.

Finally, test yourself (and get extra-credit in the bargain!) on the following chemistry concepts. Remember that you must have JavaScript enabled on your browser! If you get 9 out of 10 correct (or some multiple thereof), submit the information to me to receive extra credit.

  1. Molarity, Moles and Volume
  2. Molarity, Mass and Volume
  3. Heat and Temperature Changes for Water
  4. Heat Transfer - Water
  5. Heat Transfer - Two Samples of Water
  6. Heat Transfer - Water and Another Substance
  7. Hess's Law
  8. Thermochemical Equations
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Experiences pic Experiences: Share Your Comments on Chapter Four and Chapter Five

Feel free to explore and discuss the ideas from this module with the class. The understanding of how energy affects systems can help us to understand our own energy cycles and periods. Take time to share your thoughts with the class on Discus regarding your impressions of these concepts and as how they relate to your life.

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Practice picture Practice: Complete Problem Set #5

Please complete problem set #5 to further explore the ideas from this lesson. Problem set #5 covers several questions from Chapter 4 and Chapter 5, and it can be found here . We will discuss problems like these during recitation, so come prepared to ask and answer questions.

For additional practice, try the non-assigned problems in Chapter 4 and Chapter 5. Answers to many of those problems are listed in the back of your textbook or in the Chapter Four Student Solutions Manual or the Chapter Five Student Solutions Manual.

If you need assistance on these problems, you have several options. You can visit the Learning Success Center located above the MHCC library on the Mt. Hood Community College campus; they have tutors available to help you with your chemistry homework. You can also contact me if you have any questions.

Self Test icon Test your mastery of the subject matter by trying the self quiz for Chapter 4 and the self quiz for Chapter 5. These are ungraded tests that you can use to gauge your comfort level with these concepts.
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Return to the CH 221 Chapter Guides.
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