2006-11-19 04:48:37 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
The food is "burned" in a bomb calorimeter. The energy given off by the food causes the water to change temperature. The change in temperature of the water allows us to calculate the calorie value of the food sample.
2006-11-19 04:51:22 · answer #1 · answered by physandchemteach 7 · 2⤊ 0⤋
The answer that stated that foods are burned in a calorimeter to determine their heat of combustion is partially true.
Because of the experimental difficulties with actually doing this measurement, most of the data you see are determined by analysis of the protein, lipid, and carbohydrate content. Standard average values for protein, lipid, or carbohydrate combustion heats are then used to calculate a value which is usually close to that obtained by actual calorimeter experiments.
Remember that a dietetic calorie is 1 Kcal (1000 calories).
2006-11-19 13:27:24 · answer #2 · answered by Richard 7 · 0⤊ 0⤋
In many chemical reactions some of the energy given off is in the form of heat. The heat is measured in units called calories. One calorie is the amount of heat required to raise the temperature of 1 milliliter of water by 1 degree celsius.
2006-11-19 05:26:00 · answer #3 · answered by Anonymous · 0⤊ 0⤋