Calorie Content of Food
Purpose: The purpose of this lab was to measure the energy content of three different food items using the change in water temperatures from the heat of the food. Procedure:
1. With your digital scale determine the empty weight of your 100-mL beaker.
2. Half-fill the beaker with water (approximately 50 ml) and weigh it again.
3. The beaker and water weight minus the empty beaker weight is the net weight of water used for this experiment. Record it. 106.7-65.9=40.8g 4. Place aluminum foil on the table top to catch any spills and also to reflect heat upward.
5. Set up the burner stand over the aluminum foil and place the beaker of water on top of the burner stand
6. Measure and record the initial temperature of the water. 13 degrees Celcius 7. Marshmallow: With your digital scale determine the mass of a marshmallow and the mass of your empty fork, and record the figures.
a.Place the marshmallow on the fork and light it with a lighter or a candle.
b. As soon as the marshmallow is well lit and burning, hold it under the beaker of water while you occasionally stir the water with the thermometer.
c. When the marshmallow is completely burnt some of it may stick to the fork. Weigh the fork with the marshmallow remnants and record. Subtract the empty fork weight to obtain the weight of the unburned marshmallow residue.
d. Record the temperature of the water – this is the final temperature.
e. To analyze another food item place a fresh beaker of water on the burner stand. Don’t forget to determine the mass of the water and the initial temperature.
8. Peanut or walnut: Record the weight of the peanut or walnut. a. The peanut or walnut is best held in place by the wire test tube holder, but a long needle will also work. Food items like peanuts may take a while to stay lit and you may have to move them around in a flame to get them burning. When well-lit...