Specific Heat PreLab - Honors Chemistry

On a sunny day, the water in a lake may warm up a degree of two while the sand on the beach may
become too hot to walk on in your bare feet. This may seem strange since both the sand and the water are
being heated by the same heat source. This evidence suggests that it takes more heat to raise the
temperature of substances than others. This, in fact, is true.
The amount of heat that is required to raise the temperature of 1 gram of substance by 1 C is called the
specific heat capacity, or simply the specific heat of the substance. Water has a high specific heat (4.184
J/g C). This value is high in comparison with the specific heats of many other materials.
The amount of energy involved in changing the temperature of a sample of a particular substance depends
on three factors: the specific heat of the substance, the mass of the sample, and the magnitude of the
temperature change. Remember, T = T f – T i , so it is possible to have a negative T. Negative values
indicate the direction of the change, or heat lost to the surroundings. Also remember that the amount of
heat that is transferred in the process of producing a temperature change can be calculated by using the
following equation: q = (m
sample
)( csample )( T
sample
)
In this experiment, you will use a simple calorimeter to determine the specific heat of lead. A heated
sample of this metal will be poured into the calorimeter consisting of cool water and a foam cup.
Eventually, the water and metal will reach the same temperature. Because foam is a good insulator, heat
cannot easily escape from the calorimeter into the surroundings. Therefore, heat lost by the hot lead
should be equal to the heat gained by the cool water.
1. What is Specific heat?
2. List the three factors that determine the amount of heat energy involved in changing the temperature a
substance:
3. What happens to the heat stored in the lead shot when the shot is poured into the Styrofoam cup full of
water?
4. How will you remove the test tube of lead shot from the boiling water?
5. List the three temperature recordings that you are to make:

Procedure
As you perform this experiment, record your data in the data table.
Lead is a toxic metal. Wash
your hands thoroughly after
use!
1. Add about 250 mL of tap water to a 400 mL beaker. Place the beaker on a wire gauze on a ring
clamp. Use a gas burner to bring the water to a boil. While the water is boiling, proceed to step 2.
2. Determine the mass of a clean, dry 50 mL beaker to the nearest 0.01 g. Add about 80 grams of
lead shot (Pb) to the beaker. Record the combined mass of the shot and the beaker to the nearest
0.01 g.
3. Construct a paper funnel to carefully transfer the lead shot to the dry test tube. Be careful to add
the shot to the test tube gently so you don’t break the test tube. Suspend the test tube into the
boiling water by using a utility clamp. Be sure the lead shot is below the water level in the beaker.
Leave the test tube in the boiling water for at least 10 minutes. Proceed to step 4 while the lead
shot is heating.
4. Carefully measure out 100 mL of distilled water in a graduated
cylinder and record the actual mass that you used. Pour into a
Styrofoam cup. Place the cup into a 250 mL beaker for
stability.
Be sure to record your
temperatures to the correct
number of significant digits!
toxic metal. Wash your
hands thoroughly after use!
5. After the shot has been heating for at least 10 minutes, record the temperatures of the water in the
Styrofoam cup and the boiling water in the beaker. (We will assume that the Pb shot is now the
same temperature as the boiling water.) These temperatures are the initial temperatures for the
water and the lead.
6. Remove the test tube from the bath, using the clamp as a holder. Carefully, but quickly, pour the
lead shot into the water that is in the Styrofoam cup. Place the thermometer and a stir rod into the
cup. Gently stir with the stirring rod (NOT
the thermometer) and record the highest
temperature the of Pb-water mixture.
7. Drain the water off the shot and return to
your teacher to be dried.
8. Repeat for trial 2.
9. Carefully dry your glassware for the next
class.

Honors Chemistry
LAB: Specific Heat
Name _____________________________
Data Table TRIAL 1 TRIAL 2
Mass of 50 mL beaker
Mass of 50 mL beaker + metal
Mass of metal
Initial temperature of water in cup
Initial Temperature of metal
(temperature of boiling water)
Final temperature of metal & water
Mass of water
Data Analysis
1. Calculate the changes in temperature of the water ( T water ) and of the metal for each trial:
ΔT water :
Trial 1 Trial 2
ΔT metal :
2. Calculate the heat gained by the water in each trial. (See the Introduction for an explanation of this
calculation.)

3. Remembering that the heat gained by the water is equal to the heat lost by the metal, calculate the
specific heat of the metal for each trial:
4. Calculate your average value for the specific heat of the metal:
Results and Conclusions
1. Look up the accepted values for the specific heat of the metals and calculate the percent error in the
specific heat value that you determined experimentally.
2. Which of the data you recorded contains the greatest measurement error? Can the percent error in
your specific heat be accounted for by the error in this one measurement?
3. You assumed that the initial temperature of the lead shot was the same as that of the boiling water.
This assumption may not have been correct and may account for some experimental error. What other
assumptions were made that may be sources of error?
4. List the value for the specific heat of lead obtained by three other lab groups. Do you think this
property could be used to identify substances? Explain your answer.
5. If you were looking for a material that was a good insulator, would you prefer a material with a high
or low specific heat capacity? Explain your reasoning.