Thermodynamics Challenge

 

Purpose: To insulate a 12 oz aluminum can in order to minimize the rate of heat loss.

 

Materials:

·        You will bring

o       1 12 oz aluminum can

o       Insulation for the aluminum can

·        I will provide

o       1 thermometer

o       1 stopwatch

 

Procedure:

1.     You and a partner will obtain 1 12 oz aluminum can and surround it with some kind of insulation.

2.     Be creative in designing your insulation—you can use everyday household/common items.  The only material you cannot use is any type of material that is designed to serve as insulation i.e. fiberglass insulation, soda can insulators, etc.

3.     On Wednesday January 16, you will bring your can and insulation to class.

4.     200 mL of hot water will be poured into the can.

5.     Immediately after adding the water, place a thermometer into the can and read the initial temperature.

6.     Read the temperature every minute for 30 minutes; record the temperature in a data table.

7.     While you are taking data for your can, I will be taking data for a can with no insulation.  This will serve as our control.  In order to see if the insulation affects the rate of heat loss, we must compare the rate of loss from an insulated can (the experimental group) to the rate of heat loss from an uninsulated can (the control group).

 

Data Analysis

Once you have recorded data for both the control and the experimental cans, you will construct a graph.  Follow the guidelines below when making your graph.

·        Place a title at the top of your graph.

·        Label each axis with a title and units in parenthesis, i.e. Temperature (deg C)

·        Calibrate each axis.  On the temperature scale, you do not have to start with zero; just make sure you use a range that includes all of your data.

·        Make the graph large enough that you can see a trend in the data; if the graph is too small, you will have a difficult time interpreting your data.

·        Include both sets of data, and use a different symbol for each set of data.

·        Include a legend that indicates which symbol goes with which data set.

·        Draw a line or curve of best fit for each set of data.

 

 

Write-up

At the end of the period on Wednesday, January 16 you will turn in the write-up for this lab.  The write-up will be worth a lab report grade.  The write-up must be typed (this is to prepare you better for college) and the typing is worth 5 points.  Follow the outline below as you construct your write-up.  Divide your write-up into sections as I have done below.  All responses must be in complete sentences.

 

I.       Names of group members (2 points)

·        First and last names should be printed in the upper left hand corner, with the typer’s name at the top.

 

II.     Title  (3 points)

·        Be creative on your title.  Please do not use “Thermodynamic Challenge” as your title.

 

III.  Purpose  (5 points)

·        Why are we doing this lab?  What is the question we are trying to answer or the problem we are trying to solve?

 

II.     Hypothesis  (5 points)

·        “If – then - by” statement that includes how you intend to solve this problem.

 

III.  Materials (10 points)

·        List your materials and describe how you constructed your insulating system. 

·        Why did you choose these materials?

·        You must use scientific terminology and reasoning as you explain why you picked the materials—I want reasoning in terms of heat flow, conduction, temperature, Newton’s Law of cooling, Laws of thermodynamics, etc.  You can use your class notes and chapters 21, 22, and 24 of your book as a reference.  This section only has to be 1-2 paragraphs, but I need you to show me that you have learned something about thermodynamics and heat flow.

 

III.  Procedure (10 points)

·        In number list form, discuss the procedure you followed to carry out this experiment.  The procedure should be detailed enough for someone to follow who has not read this handout and produce similar results.  ***Include a labeled diagram of your experimental system.***

 

IV.  Data (10 points)

·        Include two data tables one with temperature readings from the experimental can (your can) and another with temperature readings from the control can (my can).  You may use one data table, but both sets of data must be present.

 

V.  Data Analysis (15 points)

·        Include a graph that contains both sets of data (when making your graph, follow the directions listed above).

·        For each set of data, calculate an average rate of heat loss.  DT/t—the change in temperature divided by time (30 minutes).  The units on heat loss are 0C/min.

·        For each set of data, calculate the rate of heat loss for each 5-minute increment.  This can be best displayed in a data table.

 

VI.  Conclusion (8 points)

·        Again, make sure you use proper scientific terminology in your answers.

·        Which group (the control or the experimental) had a lower rate of heat loss?

·        Was this what you expected?

·        Why did this group lose less heat than the other group?

 

VII.  Conclusion Questions (32 points)

·        Answer the following questions in complete sentences.  Phrase the answer so that someone can read it and know what you are talking about even if they have not read the question.

1.     Did the rate of heat loss remain constant during the 30-minute period you       took data?

2.     Should the rate of heat loss have remained constant during the 30-minute             period you took data?  Use Newton’s Law of Cooling to explain why or        why not.

3.     List at least one modification you would make to your insulation system to       improve its performance.

4.     Discuss at least one practical application of this project.  In your                   discussion, you must identify an application and explain, in depth, the       importance of this application and how it works in terms of what you have       learned through this unit.

 

 

 Link to the Rubric