Calorimetry and the Specific Heat of a Metal

Objective: To use the first law of thermodynamics in the determination of the specific heat capacity of metals.

Apparatus: Double-walled calorimeter (2 Styrofoam cups), thermometer, hot plate, beaker, string, balance, metal samples and water.

Procedure: Caution, you will be working with steam and hot metal in this lab

1. What is the First Law of Thermodynamics?
2. Of the items on the apparatus list, which one do you already know the specific heat of? What is its specific heat?
3. Think about how you calculate heat energy (Q) and then determine what values in this equation you can measure using the apparatus provided.

Calculations:

Show your calculations for the specific heat of EACH metal sample you tested.

METAL

Calculated Specific Heat

Specific Heat (true value)

Percent Error

Use http://www.chemicool.com to find the true specific heat values.

Calculate the percent error for each of your metal samples

Questions

1. Speculate ways energy can escape from, or be added to, the system?

2. How would you correct the energy conservation equation to include the energy associated with the cup (or ignore the cup if you included it)? Does including (excluding) the effect of the cup energy tend to change your measured specific heat?

3. You added energy to the sample by immersing it in boiling water. Another method would be to hold it in the steam above the boiling water. Which method is better and why?

4. To improve on the accuracy of this experiment, one can start with water that is slightly cooler than the room's temperature and end up with a final equilibrium temperature that is slightly warmer than room temperature. Why might this improve the accuracy of your result?

5. List all the ways liquid water contains energy (Hint, imagine starting with no energy, or the minimum energy possible, and adding energy to get to where you want)?

6. Is it possible to test energy conservation without knowing how much energy the objects involved contain?