1. OBJECTIVE
This experiment deals with phenomena arising from the exchange of thermal energy between bodies. During the experiments, you will determine the thermal capacity of a calorimeter and, later, use this data to determine the specific heat of various substances. As part of the activities you will have to assemble and adjust the equipment and instruments necessary to carry out the experiment.


At the end of this experiment, you should be able to:

describe the phenomena caused by the heating of a specimen or substance;

illustrate how thermal equilibrium occurs between solid and liquid substances;

determine the heat capacity of a calorimeter;

determine the specific heat of a substance.

2. WHERE TO USE THESE CONCEPTS?
In nature, energy is found in different forms. One of them, perhaps the most important, is heat. We define heat as thermal energy in transit that flows from one body to another as a result of the difference in temperature between them. Heat exchanges between bodies and objects happen all the time. A simple example is a hot cup of coffee that is left on a meeting table. Some time later, the coffee will be at the same temperature as the room.

Heat exchange occurs in three ways: by convection, conduction or radiation. Without realizing it, in our daily lives we experience situations typical of these three cases. Air conditioning devices are almost always installed in the upper part of the walls of a room, due to the fact that while the cold air descends, the hot air rises (convection). When we hold the metal handle of a pan on a lit stove, we feel it hot. When we feel that the wall of the house is hot at night, after a day of high temperatures during the day (driving). When we place our hand close to one of the hot burners on a stove, we immediately feel heat (irradiation).

Thermal machines, such as steam engines, combustion engines, air conditioners, refrigerators, solar energy collectors, among hundreds of other examples, demonstrate the importance of the topic of calorimetry.


3. THE EXPERIMENT
In this experiment you will use the calorimeter to determine the specific heat of water and vegetable oil. In the first phase of the experiment, you will determine the heat capacity of the calorimeter. Then, based on the calorimeter data, you will determine the specific heat of a vegetable oil.


4. SECURITY
The experiment was designed not to pose any physical risks. However, as this practice involves the use of heated water and oil, the experiment can only be carried out if you are wearing a lab coat to protect your body and protective glasses to avoid splashing hot water and oil into your eyes.


5. SCENARIO
You will find on the bench the calorimeter, a 500mL beaker, thermometer, heating system, thermos flask, a scale and bowls containing water and cooking oil.