Specific Heat Capacity of a Piece of Metal

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Determining the Specific Heat Capacity of an Unknown Metal
(Lab Guidelines: 1,2,3,4,5&6[attach handout],7,9,10,11,12)
Purpose: To determine the identity of a piece of unknown metal by using Heat Gained = Heat Lost, and
the equation Q=CmT to calculate the specific heat capacity of a metal.
Intro Info:
What is Specific Heat Capacity?
What does Heat Gained = Heat Lost mean?
Materials: piece of unknown metal, Bunsen burner, ring stand ring clamp, wire gauze, 250 mL beaker,
water, Styrofoam cup, crucible tongs, Temperature Probe
Procedure:
1. Fill in the specific heat capacity of liquid water in your data table.
2. Using the balance, RECORD the mass of the piece of metal.
3. Carefully place the metal in an empty 250 mL beaker.
4. Fill the beaker ¾ full of tap water.
5. Set up ring stand, clamp, wire gauze and burner. Light burner.
6. Bring beaker of water to a steady boil.
7. Using the balance tare a Styrofoam cup and pour in about 100 grams of water. RECORD the
exact mass of the water.
8. One the water in the beaker is boiling steadily, use the temperature probe, to RECORD the
temperature of the boiling water. We can assume that this is the initial temperature of the metal.
9. Using the probe, now RECORD the temperature of the water in the Styrofoam cup. This is the
initial temperature of the water in the cup.
10. Using crucible tongs, transfer the piece of metal from the boiling water into the Styrofoam cup as
quickly as possible. Stir the water with the temperature probe until the temperature remains
constant.
11. RECORD the final temperature of the water. We can also assume that this is the final temperature
of the metal.
12. Make sure you have all values filled in for the data table below. There should be only one value
that is not filled in yet. What is it??
Data Table: WHERE IS THE QUESTION MARK???
Water in Styrofoam Cup
Mass
Specific Heat Capacity
Initial Temperature
Final Temperature
Metal
Calculations:
1. Using Q=CmT calculate the heat energy gained by the water.
2. How much heat energy was lost by the metal?
3. Based on the principle of Heat Gained = Heat Lost, use Q=CmT to calculate the specific heat
capacity of the metal.
4. Use the following specific heat capacity chart to identify the piece of metal. What is your metal?
Metal
Specific Heat (J/g*C)
Aluminum
0.900
Copper
0.385
Lead
0.129
Iron
0.449
Tin
0.228
Zinc
0.388
Question:
A 55.0 gram piece of metal is heated in boiling water to a temperature of 100.0 C. It is then transferred
to a calorimeter containing 40.5 grams of water at an initial temperature of 23.0 C. The temperature of
the water increases to 26.1C. Determine the specific heat capacity of this metal (include units!). Use the
chart above to determine the identity of the metal.
Error Analysis: Once given the identity of your metal and its specific heat capacity, calculate your
percent error for the specific heat capacity of the metal. Discuss any sources of error that could have
occurred.
Conclusion: Write a conclusion which demonstrates that you understand what you did. How did you
accomplish the purpose? Discuss the math as well.
Explain how you used the idea of Heat Lost = Heat Gained to achieve your objective and complete your
calculations.
Remember, here is a great guide for writing your conclusion:
1) Restate the purpose
2) Summarize the procedure and data collection
3) Discuss any important principles / equations used
4) Explain the graphs and/or math
5) Report your results
Also, please include any other interesting information you would like to add.
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