PASCO TD-8557 User Manual
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Instruction Manual and
Basic Calorimetry Set
TD-8557
Experiment Guide
012-03060D
CALORIMETER
MAX TEMP: 100°C
P/N: 650-02975
Al
Cu
Pb
Table of Contents
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Notes on Calorimetry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Experiment 1: What is a Calorie? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Experiment 2: Specific Heat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Experiment 3: Latent Heat of Vaporization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Experiment 4: Latent Heat of Fusion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
ii
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CALORIMETER
MAX TEMP: 100°C
P/N: 650-02975
1
Basic Calorimetry Set
TD-8557
3
2
6
45
Included Parts
1. Calorimeters, 6 pieces
2. Water trap with plastic tubing
3. Aluminum sample
4. Copper sample
5. Lead sample
6. Thermometer
Introduction
Understanding calorimetry is the first step into the field of thermodynamics, the study of the role of heat in physical
processes. With the addition of a balance, ice, and a heat source, such as PASCO’s Model TD-8556 Steam Generator,
this Basic Calorimetry Set provides the equipment necessary to perform a variety of calorimetry experiments. Four
important, introductory experiments are described in this manual:
Experiment 1: What is a Calorie? An introduction to the ideas of temperature and heat, and a demonstration
of the conservation of energy.
Experiment 2: Thermal Capacity and Specific Heat The specific heats of aluminum, copper, and lead are
measured.
Experiment 3: Latent Heat of Vaporization The role of heat transfer in the conversion of steam into water is
investigated.
Experiment 4: Latent Heat of Fusion The role of heat transfer in the conversion of ice into water is investigated.
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Basic Calorimetry Set
Notes on Calorimetry
A calorimeter is a vessel or device that thermally isolates an experiment from its surroundings. Ideally, this means that the results of an experiment performed in a calorimeter are
independent of the temperature of the surroundings, because no heat flows into or out of
the calorimeter.
However, no calorimeter is perfect, and there is always some unwanted and unaccountable
heat flow affecting the results of any calorimetric experiment. To minimize unwanted heat
flow, always plan the experiment to follow these rules:
1. The time between the taking of initial and final temperatures is minimal.
In other words, do the critical portion of the experiment quickly, so there is minimal time
for unwanted heat flow between measurements. (Don’t rush; just plan carefully.)
2. Whenever possible, room temperature is approximately midway between
the beginning and ending temperatures of the experiment. When the experi-
mental temperature is colder than room temperature, heat flows from the surroundings
into the calorimeter. When the experimental temperature is hotter than room temperature,
heat flows from the calorimeter into the surroundings. If the experimental temperature
varies above and below room temperature by equal amounts, the heat gained and lost to
the environment will be approximately equal, minimizing the net affect on the experiment.
3. Mass measurements of liquids are made as near the critical temperature
measurements as possible. This reduces the effects of mass loss by evaporation.
Measuring liquid masses by taking appropriate differences is a useful technique (see the
instructions in the individual experiments).
NOTE: In applying the above rules, it is often helpful to perform a quick preliminary experiment to
determine the best choice for initial masses and temperatures.
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Basic Calorimetry Set
Experiment 1: What is a Calorie?
Equipment Needed
• Calorimeters, 2 pieces
• Thermometer
• Balance
• Hot and cold water
Introduction
When two systems or objects of different temperature come into contact, energy in the
form of heat is transferred from the warmer system into the cooler. This transfer of heat
raises the temperature of the cooler system and lowers the temperature of the warmer system. Eventually the two systems reach some common, intermediate temperature, and the
heat transfer stops.
The standard unit for measuring heat transfer is the calorie. A calorie is defined as the
amount of energy required to raise the temperature of one gram of water from 14.5° C to
15.5° C. However, for our purposes, we can generalize this definition by simply saying
that a calorie is the amount of energy required to raise the temperature of one gram of
water one degree Celsius (the variation with temperature is slight).
In this experiment, you will combine hot and cold water of known temperature and mass.
Using the definition of the calorie, you will be able to determine the amount of heat energy
that is transferred in bringing the hot and cold water to their final common temperature,
and thereby determine if heat energy is conserved in this process.
Procedure
1. Determine the mass of the empty calorimeter, M
2. Fill the calorimeter about 1/3 full with cold water. Measure the mass of the calorime-
ter and water together to determine M
cal + water cold
3. Fill a second calorimeter approximately 1/3 full of hot water. The water should be at
least 20° C above room temperature. Weigh the calorimeter and water together to
determine M
4. Measure T
cal + water hot
and T
hot
. Record your result
, the temperatures the hot and cold water, and record your
cold
results.
5. Immediately after measuring the temperatures, add the hot water to the cold water and
stir with the thermometer until the temperature stabilizes. Record the final temperature of the mixture, T
final
.
6. Measure the final mass of the calorimeter and mixed water, M
. Record your result in Table 1.1.
cal
. Record your result.
.
final
7. Repeat the procedure twice with different masses of water at different temperatures.
(You might try adding cold water to hot instead of hot to cold.)
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