ET 3810 – THERMODYNAMICS: CALORIMETER PROJECT
The following are the guidelines and brief instructions for the project. Every team is required to elaborate on each item and turn in a detailed professionally prepared report. You must use only MS Word, Excel and/or PowerPoint as necessary to write your report. All drawings must be created using AutoCAD or Inventor. Hand-written text or drawings will not be accepted.
Objective: To build and test a calorimeter to determine the latent heat/energy of fusion of ice
Equipment: A typical calorimeter consists of the following parts as shown in the hand-drawn sketch
- One outside larger container for the water bath or the bulk of water
- One inside smaller container to hold the ice cubes
- One stirrer with a paddle placed in the outside larger container to stir the water periodically for maintaining a uniform water bath temperature
- One thermometer (preferably digital for accurate recording) to measure the water bath temperature
- A Plexiglas lid to serve as an inspection window and to prevent heat transfer between the calorimeter and its surroundings
- Conduct the experiment indoors away from heat or cold source
- Place the ice cubes in the inside smaller container. Do not use crushed ice.
- Pour cold water into the outside larger container. Do use hot or refrigerated water
- Insert and secure the thermometer and the stirrer.
- Assemble the lid and insulate the outside larger container thoroughly
- Periodically and very slowly stir the water bath
- Record the water bath temperature at regular time intervals such as 1 min, 3 min, 5 min,..
You may have to conduct a couple of trial tests to get a good idea of the time interval
- Periodically check the ice to see if it has completely melted
- Conduct at least two tests after the initial runs and enter the data in a time temperature table as shown below. Stop the experiment when the ice has completely melted or you don’t see any change the water bath temperature
Calculations and graphs:
- Plot the time-temperature graphs using your tabulated data with time as the horizontal axis and temperature as the vertical axis. The graph should smooth with the temperature gradually decreasing with the increasing time.
- Calculate the latent heat/energy of ice using the following equation while keeping the units consistent.
- Compare your calculated latent heat/energy value with the standard value available in the textbook or on the Internet.
- Conduct the experiment again if your Lice value is greater or smaller than the standard value by 10%.
Determining the mass of the water bath and the ice:
- You can use the scale to measure these two quantities
- Alternatively you can use a measuring cup to determine the two masses knowing that one cubic centimeter (cc) or one milliliter (ml) of water has a mass of one gram. Of course, you need to wait until the end of the experiment when ice is completely melted.
CALORIMETER PROJECT PRESENTATION
Five minutes presentation by each team
All members are to present a part of the project
- Demonstrate your calorimeter: Show the following
- Outside and inside containers
- Discuss the experiment
- Show at least two time-temperature tables and graphs
- Show the equation you have used to calculate the latent heat of fusion of ice
- Compare your computed value of the latent heat with the standard value available in the textbook or on the Internet
- Discuss the results and explain the discrepancies