Respuesta :
From the coffee cup to the thermometer
The assumption behind the science of calorimetry is that the energy gained or lost by the water is equal to the energy lost or gained by the object under study. So if an attempt is being made to determine the specific heat of fusion of ice using a coffee cup calorimeter, then the assumption is that the energy gained by the ice when melting is equal to the energy lost by the surrounding water. It is assumed that there is a heat exchange between the iceand the water in the cup and that no other objects are involved in the heat exchanged. This statement could be placed in equation form as
Qice = - Qsurroundings = -Qcalorimeter
The role of the Styrofoam in a coffee cup calorimeter is that it reduces the amount of heat exchange between the water in the coffee cup and the surrounding air. The value of a lid on the coffee cup is that it also reduces the amount of heat exchange between the water and the surrounding air. The more that these other heat exchanges are reduced, the more true that the above mathematical equation will be. Any error analysis of a calorimetry experiment must take into consideration the flow of heat from system to calorimeter to other parts of the surroundings. And any design of a calorimeter experiment must give attention to reducing the exchanges of heat between the calorimeter contents and the surroundings.
The energy calculated while dealing with the calorimeter experiment are the latent heat of vaporization, latent heat of fusion and the heat required to change the temperature of the substances.
Further Explanation:
The calorimeter works on the principle of conservation of energy. The amount of heat given by one part of the system is equal to the amount of heat gained by another part provided that the calorimeter does not loss any heat to the environment.
Consider that ice is mixed with water at some temperature. Then the water being at higher temperature losses heat to the ice at lower temperature. The ice gains the heat from the water and the system reaches an equilibrium at which the solution of ice and water has the same amount of energy at a particular temperature.
The different types of energies dealt with in the calorimetry experiment are as follows:
Latent heat of fusion:
The amount of energy required by a body when it is melted from its frozen state or freezes from its melted state is termed as the latent heat of fusion.
For example:
The small amount of ice is mixed with water in a calorimeter. Here, the ice requires the latent heat of fusion that leads to the melting of ice and converts it into water.
Latent heat of vaporization:
The amount of heat required to convert one gram of liquid to vapor without raising its temperature is known as latent heat of vaporization.
For example:
The water is boiling at in a calorimeter. Here, the water requires latent heat of vaporization which leads to the vaporization of water and convert it into vapors.
Thus, the latent heat of fusion, latent heat of vaporization and the heat required to change the temperature of the substance are the energies measured with the calorimeter.
Learn more:
1. Transnational kinetic energy https://brainly.com/question/9078768.
2. Expansion of gas https://brainly.com/question/9979757.
3. Conservation of momentum https://brainly.com/question/9484203.
Answer Details:
Grade: College
Subject: Physics
Chapter: Heat and Energy
Keywords:
Heat, energy, calorimeter, latent heat, vaporization, fusion, experiment, temperature, melting, boiling, liquid, vapor, evaporation, condensation, freeze.
