Calorimetry Essay

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I. Introduction Calorimetry is a used to determine the amount of heat transfer in a chemical reaction. It can measure one of two things: the amount of heat that is absorbed (in an endothermic process) or the amount that is gained (in an exothermic process). To conclude the calorimetry of a substance, the equation below is used: Eq. 1 q= Cs x g x T Q represents heat. Specific heat (Cs) is multiplied to the mass (g) and temperature change that occurred in the reaction. ( T). Specific heat is defined as the amount of energy required to raise the temperature of 1 g of a substance by 1 K, under a constant pressure. Considering the fact that substances have differences, the specific heat varies depending on what substance is being heated. Calorimetry is performed with a calorimeter. These can be intricate and expensive devices, but in this lab, two Styrofoam cups are used. The purpose of this experiment is to calculate the specific heat of a foreign metal. To do this, the metal will be heated, and then put into water to determine the heat transferred. The heat that is transferred from the metal to the water is measured using the equation: Eq. 2 q(water) = -q(metal) The heat of water is positive because it was initially cold, and because the hot metal was being added to it, it gained heat. The heat of the unknown metal is negative because of the loss of heat it is experiencing when submerged in cold water. The specific heat constant for water, 4.184 J/g C, is used for this equation. The specific heat can be found by using The Law of Dulong and Petit: Eq. 3 Cs(aluminum) = slope x 1/atomic weight This equation is used to find specific heat from the graph that will be drawn based on the results of the metal specific heats. II. Materials and Procedure See General Chemistry 101/102 Laboratory Manual (pg. 69) for detailed list of
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