Understanding the definitions of heat and work A mixture of gaseous reactants is put into a cylinder, where a chemical reaction turns them into gaseous products. The cylinder has a piston that moves in or out, as necessary, to keep a constant pressure on the mixture of 1 atm. The cylinder is also submerged in a large insulated water bath. (See sketch at right.) 1 atm pressure piston cylinder From previous experiments, this chemical reaction is known to release 135. kJ of energy. water bath The position of the piston is monitored, and it is determined from this data that the system does 242. kJ of work on the piston during the reaction. gases do O exothermic O endothermic Is the reaction exothermic or endothermic? O up Does the temperature of the water bath go up or down? O down O neither O in Does the piston move in or out? O out O neither O in Does heat flow into or out of the gas mixture? O out O neither How much heat flows? Be sure your answer has the correct number of significant digits. II

Understanding the definitions of heat and work A mixture of gaseous reactants is put into a cylinder, where a chemical reaction turns them into gaseous products. The cylinder has a piston that moves in or out, as necessary, to keep a constant pressure on the mixture of 1 atm. The cylinder is also submerged in a large insulated water bath. (See sketch at right.) 1 atm pressure piston cylinder From previous experiments, this chemical reaction is known to release 135. kJ of energy. water bath The position of the piston is monitored, and it is determined from this data that the system does 242. kJ of work on the piston during the reaction. gases do O exothermic O endothermic Is the reaction exothermic or endothermic? O up Does the temperature of the water bath go up or down? O down O neither O in Does the piston move in or out? O out O neither O in Does heat flow into or out of the gas mixture? O out O neither How much heat flows? Be sure your answer has the correct number of significant digits. II

Living by Chemistry

2nd Edition

ISBN:9781464142314

Author:Angelica M. Stacy

Publisher:Angelica M. Stacy

ChapterU5: Fire: Energy , Thermodynamics, And Oxidation-reduction

Section: Chapter Questions

Problem 4STP

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