THERMOCHEMISTRY PROJECT OVERVIEW

INTRODUCTION:

You are no doubt familiar with the idea of things being hot or cold. Car engines are hot when you run them. The inside of a refrigerator is cold when you run the refrigerator. When you activate a sports pack, some become very cold and some become hot. When you stand in the sun you feel warm, when you stand in the snow you feel cold. When you engage in sports or other physical activities, you feel warm. When you eat, you feel warm and when you're done, you sometimes feel cold. Why is this? What is going on chemically to cause the effects described above? The study of energy change is known as thermodynamics. Energy changes associated with chemical reactions, such as in combustion, is called thermochemistry.

Topics on thermochemistry and thermodynamics are very important. Most reactions give-out or take-in energy as bonds break or new bonds form; this is usually accompanied by a temperature change. It is important to look at the processes and at terminology behind what is happening when things heat up or cool down and at the useful applications we can find for hot and cold things.

The material from this unit can be broken down into nine major concepts. As a group you will be responsible for learning your concept and teaching that material to the class in a clear concise manner. You will present your information using multimedia in combinations of flash, PowerPoint, and video. You will provide some form of notes outline, and you will assess your classmates’ comprehension of this material with a worksheet designed and graded by your group. Some of the groups will also be responsible for locating, setting up, and overseeing a lab.

TASKS:

1. Research/Learn: You will find a list of your learning objectives and information you need to cover for each section in the handout on your section of the material. I am here to guide you and to help you if you are totally clueless about something. I am also here as a resource for you to use any way you need to (within reason). You need to learn as much as you can about the material you are assigned and organize it into a logical sequence. You need to find the information from at least 4 sources, one of which will be a textbook, which may be your primary source, and one of which must be a website. You will need to locate the website and the two other sources.

2. Presentation: You and your group need to organize, design, prepare, and present your material that you researched and learned with PowerPoint. A PowerPoint presentation, can be as fancy as you'd like or, as fancy as time would allow. DO NOT SACRIFICE THE MATERIAL BY SPENDING TOO MUCH TIME ON BELLS AND WHISTLES. I do expect it to be thorough and coherent. If there is a concept that you aren't comfortable with then you can't teach it to someone else. Come to me and let me try to clear it up for you. The PowerPoint presentation can be as long as you need to make it. I would think anywhere between 12 and 24 slides is reasonable. Keep in mind it's not a limit that decides the number of slides; it's the material. I expect examples, definitions, pictures, real world connections, and charts if necessary to present the material. We are your students; you are the teachers…so teach us.

3. Notes: You need to provide me with a notes sheet(s) that goes along with your presentation for your students to fill in as you present the material. The type of handout is up to you all, but something needs to be available for your students. How interactive you make the handout is up to you, but I don't expect it to be a completed set. Your students need to be involved in the presentation in some way.

4. Worksheet: You need to assess the learning of your students. To do that you will need to type up a worksheet for me to copy off for your classmates. This worksheet should correlate directly to your lesson and can be in any format you choose (except word searches or mazes). It needs to be a relevant length (one page front) for the average student to do, and should be appropriately challenging. You as a group will also have to grade the worksheet. NOTE: You might find it useful to design the worksheet before you design the presentation. This is a good strategy to make sure that you cover the material in an appropriate manner.

5. Evaluation of Group: This is where you get to vent about your group. This will be an anonymous format and you get to tear into your group's dynamics and participation. Or you get to praise your members for their participation and their efforts to accomplish the tasks assigned. This will be a written reflection on the effort put out by your group and your opinion on how well your group worked together. I will give you a set of questions to answer about your group. I will also use your opinions and my observations to determine the participation grade for each student.

GRADES:

This project will take three blocks to prepare the lesson and worksheet and then a couple of blocks to present the material and do other necessary activities. The rhythm of the presentations will be up for debate. We'll just wait and see. There are several things that I will be working with you on for your overall grade. This is your whole chapter's worth of grade, with the exception of the assessment.

Here's how it will break down:

Participation -- 50% (100pts) -- Your participation has a group component (25%/50 pts) and an individual component (25%/50 pts). This is participation in research, setting up presentation, designing the worksheet, supervising labs if appropriate, AND presenting material.

Presentation -- 35% (70pts) -- How logically the presentation is set up (10%/20 pts), How thoroughly material is covered (15%/30 pts), and Amount of effort used to understand material well enough to teach it (My call) (10%/20pts)

Worksheet -- 15% (30pts) -- How well it correlates with material covered (8%/16 pts), Amount of material assessed (4%/8 pts), Appropriateness -- Challenging but not impossible (3%/6 pts)

TOPICS:

These are the topics that will be covered during this project. You will draw one of the topics to research, learn, and to teach. You are only responsible for teaching your topic. Once you have drawn your topic, you can pick up a sheet to give you some direction.

1) Endothermic Vs. Exothermic Reactions

2) Bond Energy

3) Enthalpy and Change in Enthalpy

4) Heat Capacity and Specific Heat

5) Determining Heat of Reaction: Hess's Law

6) Determining Heat of Reaction: Enthalpies of Formation

7) Determining Heat of Reaction: Calorimetry

8) Stoichiometry and Heat of Reactions

9) Heat Curves

1) ENDOTHERMIC VS. EXOTHERMIC

Chemical reactions are classified as either endothermic or exothermic. It is your responsibility as a team to research about endothermic and exothermic reactions, and what that means. It is an important cog in the wheel that we are attempting to produce, and will establish the most basic connection between chemical reactions and energy. The minimum concepts that should be addressed and explored are (not in any particular order):

What does endothermic mean?

What does exothermic mean?

How do we graph the reactions progress?

How does the endothermic progress curve differ from the exothermic progress curve?

How are reactions classified as endothermic or exothermic?

What is activation energy?

You are going to introduce the topic as the foundation of Thermochemistry. The other groups build on this concept. You need to be thorough and clear. I will help you with whatever you might need. If you choose to do a lab, just let me know and we'll check to see if it is feasible. You might find a lab or two on Endothermic and Exothermic Reactions. Your worksheet should concentrate on the concept of endothermic and exothermic reactions and how we graph the reactions. It will mostly address definitions, but something you might try is having them identify an exothermic reaction given the enthalpies.

2) BOND ENERGY

Bond energy is the measure of the stability of a chemical bond. This is a very useful measure of the strength of a chemical bond. I’d like you to explore this concept wherever it leads you. The minimum concepts that should be addressed and explored are (not in any particular order):

What is the bond energy?

What is the coulomb force?

How is the bond energy used?

How is the bond energy measured?

What does bond length have to do with bond energy?

How do bond strengths compare in ionic and covalent bonding?

How do the various types of covalent bonds compare in bond strength?

You have a fairly big piece of the pie so it's important to be thorough and clear. I will help you with whatever you might need. Your worksheet should concentrate on the concepts presented and won't include any calculations. If you don't understand your topic, then you need to talk to me; if you don't understand it then you can't teach them.

3) ENTHALPY AND CHANGES IN ENTHALPY

The enthalpy change for a chemical reaction is equal to the heat absorbed or gained during the reaction. It is as the

name implies a change in one enthalpy to another, and is represented by the symbol H. Your job is to find as much information as you can on change in enthalpy and to talk with each other and me until you understand it. Topics that should be addressed and explored are (not in any particular order):

What is a state function?

What is enthalpy?

How is enthalpy measured?

How is enthalpy represented?

What is meant by enthalpy change?

How do we diagram Enthalpy changes?

What is standard state, Standard Enthalpy change?

How do we calculate with enthalpy changes?

How do we use Enthalpy?

What is the sign convention of enthalpy changes?

You need to be thorough and clear. I will help you with whatever you might need. If you choose to do a lab, just let me know and we'll check to see if it is feasible. You'll look for labs that talk about changes in enthalpy. There won't be an abundance of options, but we might find one or two to choose from. Your worksheet should concentrate on the change in enthalpy. It will mostly address calculations and concepts. If you don't understand how to do the calculations, then you need to talk to me; if you can't do them, then you can't teach them.

4) EXPLORATION OF HEAT CAPACITY AND SPECIFIC HEAT

Every object absorbs heat differently from every other object. The amount of heat energy an object absorbs to raise its temperature one degree is the heat capacity of the object or its capacity to hold or gain heat. The amount of heat energy needed to change the temperature of 1.00 g of a substance one degree in temperature is called the specific heat capacity or, simply, specific heat. Your job is to find as much information as you can on heat capacity and specific heat and to talk with each other and me until you understand it. Topics that should be addressed and explored are (not in any particular order):

What is heat capacity?

How do we write it mathematically?

What is the difference between heat capacity and specific heat?

How do we use specific heat?

How do they relate to a quantity called molar heat capacity?

What do latent heat of fusion and vaporization have to do with it all?

Your topic isn't too complicated, but it's important to be thorough and clear. I will help you with whatever you might need. If you choose to do a lab, just let me know and we'll check to see if it is feasible. You'll look for labs that deal with heat capacities. There are a couple of good ones that define the specific heat of water if that interests you. You might share a lab with the calorimetry folks. Your worksheet should concentrate on the concept of heat capacity, and what that means. It should also address calculations and concepts. If you don't understand how to do the calculations, then you need to talk to me; if you can't do them, then you can't teach them.

5) DETERMINING HEAT OF REACTION: HESS'S LAW

Germain Hess discovered in his explorations of energy, that if a series of reactions were added together, the enthalpy change for the net reaction would be the sum of the enthalpy changes for the individual steps. This really makes a big difference if one reaction can't be accomplished safely. If you can accomplish two other reactions and follow the rules, you can find the answer to your questions. Your job is to find as much information as you can on heat capacity and specific heat and to talk with each other and me until you understand it. Topics that should be addressed and explored are (not in any particular order):

What is Hess's Law?

How does that work really?

What does the conservation of energy have to do with it?

How do we diagram Hess's Law?

How do we apply Hess's Law?

What are the rules to using Hess's Law?

How do we use those rules to solve Hess's Law problems?

This is a very important and useful topic. It is a Law that has tremendous potential for chemists. It's important to be thorough and clear in your calculations and in your explanations of how it works. I will help you with whatever you might need. If you choose to do a lab, just let me know and we'll check to see if it is feasible. There will only be a couple of labs to choose from and you might find them too complicated to try in the time we have, but you'll look for labs that deal with Hess's Law. Your worksheet should concentrate on the concept of Hess's Law, and what that means. It should mostly be problems rather than concepts. If you don't understand how to do the calculations, then you need to talk to me; if you can't do them, then you can't teach them.

6) DETERMINING HEAT OF REACTION: ENTHALPIES OF FORMATION

Standard enthalpies of formation can be used to calculate the energy released or absorbed in a chemical reaction. It is a practical use of years of data generated by scientists. Your job is to find as much information as you can about standard states and the usefulness of standard enthalpies of formation in determining the heat of a reaction. You should talk with each other and me until you understand it. Topics that should be addressed and explored are (not in any particular order):

What is a standard enthalpy of formation?

What is meant by standard state?

How do we symbolize a standard enthalpy of formation?

How can standard enthalpies of formation be used to calculate the change in enthalpy of a reaction?

What pure substances don’t have a standard enthalpy of formation, and why not?

This is a very important and useful topic. These standard enthalpies are the values commonly used in calculating the heat energy transferred in the reaction. It's important to be thorough and clear in your calculations and in your explanations of how it works. I will help you with whatever you might need. Make sure you use examples to help you teach the concept. Your worksheet should relate to the examples that you used. It should mostly be problems rather than concepts. If you don't understand how to do the calculations, then you need to talk to me; if you can't do them, then you can't teach them.

7) DETERMINING HEAT OF REACTION: CALORIMETRY

Chemists measure the enthalpy change of a reaction with calorimetry. This is the study of heat flow and heat measurement. It is the method used by chemists to find out the amount of energy needed to burn up a certain amount of food. This is the primary source of the calorie information on a food label. Your job is to find as much information you can about calorimetry and calorimeters. You need to talk with each other and me until you understand it. Topics that should be addressed and explored are (not in any particular order):

What is a calorimeter?

What are the types of calorimeters?

What does each look like?

How does one work?

What important values are necessary to use a calorimeter?

What kinds of calculations can be done with the information found?

How are they most often used?

This is a very important and useful topic that is extremely useful for measuring enthalpy changes. It is a method that is used to come up with the standard enthalpy values used in calculations. It's important to be thorough and clear in your definitions and in your explanations of how it works. I will help you with whatever you might need. If you choose to do a lab just let me know and we'll check to see if it is feasible. There are some easy labs that use the simplest of calorimeters to get very good results. You would have several to choose from. Your worksheet should concentrate on concepts rather than problems, although a problem or two would not be inappropriate. This is a concept that needs careful attention, and needs to be understood by the entire class.

8) STOICHIOMETRY AND HEAT OF REACTIONS

That’s right, I said stoichiometry. You and your group will need to discuss how stoichiometry is used to measure the connection to a given amount of reactant and the energy that will be used or produced by the reaction. This won’t be an especially involved amount of material, but I expect to see examples and maybe some classwork on this topic. Topics that should be addressed and explored are (not in any particular order):

How can stoichiometry be used to connect reactants or products to energy?

How can stoichiometry be used in tandum with heats of formations to calculate the energy of a reaction?

This is a simple, but important, concept. Your biggest challenge will be in finding 4 resources. There isn’t a whole lot to present with this topic, but it has lots of possibilities for calculations and worksheets. I will help you with whatever you might need. There aren’t might even be some labs you could do. Your worksheet should involve stoichiometrically using given enthalpies to calculate total heat of reaction.

9) HEAT CURVES AND HEAT OF PHASE CHANGES

This is actually an interesting and somewhat involved set of material. You will explore the amount of energy to take ordinary liquids and solids through there phase changes, either by removing energy or supplying energy. There are quite a few calculations involved in calculating the quantity of heat involved in phase changes, but they are basically the same no matter what substance you start with. Topics that should be addressed and explored are (not in any particular order):

What are the changes of state?

Which changes involve a removal of energy?

Which changes involve an addition of energy?

What is the heat of fusion?

What is the heat of vaporization?

What is a heat curve?

What are the segments of a heating curve?

How do we calculate the energy of a phase change?

How do we calculate the energy before and after a phase change?

This is a great topic. You won’t have any trouble finding information and examples to help you learn about these energies. You might not have ever considered how much energy it takes to boil a pan of water dry, but that doesn’t mean you shouldn’t know how to calculate it. Your worksheet should have multi-step problems where you not only have to heat up or cool down the substance, but also change its phase. There might even be a lab on this topic that can be fairly simple to do, but also be very effective as a teaching tool.