Lab Report Testing Reactions with a Calorimeter

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Lab Report Testing Reactions with a Calorimeter A team was sent to the chemical manufacturing division of a small chemical company to help the technicians with experiments. Since the notes written by the technicians were inaccurate and unfinished, all of the experiments they had preformed needed to redone and documented correctly. The head of the company gave the new team the task of trying to figure out why some chemical reactions caused the reaction vessel to get cold and others caused the vessel to get hot. The group constructed ¡°an apparatus to measure the quantity of thermal energy gained or lost during the chemical reactions¡± (Bellama, 193). This device was called a calorimeter. A series of different reactions were conducted using two different calorimeters. First, hot and cold water tests were preformed. Based on these results the scientists calculated the heat capacities of the calorimeter. The density and specific heat of pure water were used for these calculations. The other tests that were redone and recalculated were: salts in water, precipitation reactions, and acid base reactions. Then the question of whether the solution absorbed or gave off heat can be answered. Also, whether or not the concentration of an acid base reaction made a difference in the heat absorbed or lost can then be resolved. The goal is to determine if the reactions gave off heat or became cold. The factors that affect heat energy changes were identified (Cooper, 103). The results for the heat capacities of the calorimeters were determined using the hot and cold water tests. Data was gathered from this experiment and calculations were preformed that resulted in the figures shown in table 1. Table 1 ¨C Heat Capacity of C... ... middle of paper ... ...eter Two. The initial temperature of the hydrochloric acid was recorded. Twenty milliliters of sodium hydroxide were measured into a graduated cylinder and added into the calorimeter. The temperature was immediately recorded. The solution was monitored, and the temperature was recorded every ten seconds until it began to decrease. The solution was properly disposed of. The above procedure was repeated two more times using 3 M and 6 M concentrations of hydrochloric acid and sodium hydroxide. All results were observed and recorded, and the solutions were properly disposed of. Equations in the lab manual were used to calculate the ∆H for each experiment. Bibliography: Bellama, Jon. General Chemistry: Third Edition. New York: Brooks/Cole Publishing Company, 1999. Cooper, Melanie. Cooperative Chemistry. New York: McGraw-Hill, 1995. 60-62.

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