1. (a) The number of kilocalories in food is determined by calorimetry techniques in which the food is burned and the amount of heat transfer is measured. How many kilocalories per gram are there in a 5.2 -g peanut if the energy from burning it is transferred to 0.5 kg of water held in a 0.12 -kg aluminum cup, causing a 54.3 °C temperature increase? The specific heat of water is 1.00 kcal/kg °C, and the specific heat of aluminum cup is 0.215 kcal/kg °C. Q kcal/g p (b) Compare your answer to labeling information found on a package of peanuts and comment on whether the values are consistent. A label for unsalted dry roasted peanuts says that 30 g contains 175 calories (kcal). Find the (Q/m) from calorimetry techniques of the label on a box of roasted peanuts. Q m cal Q m label
Energy transfer
The flow of energy from one region to another region is referred to as energy transfer. Since energy is quantitative; it must be transferred to a body or a material to work or to heat the system.
Molar Specific Heat
Heat capacity is the amount of heat energy absorbed or released by a chemical substance per the change in temperature of that substance. The change in heat is also called enthalpy. The SI unit of heat capacity is Joules per Kelvin, which is (J K-1)
Thermal Properties of Matter
Thermal energy is described as one of the form of heat energy which flows from one body of higher temperature to the other with the lower temperature when these two bodies are placed in contact to each other. Heat is described as the form of energy which is transferred between the two systems or in between the systems and their surrounding by the virtue of difference in temperature. Calorimetry is that branch of science which helps in measuring the changes which are taking place in the heat energy of a given body.
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