O THERMOCHEMISTRY Understanding the definitions of heat and work ARL 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 The temperature of the water bath is monitored, and it is determined from this data that 169. kJ of heat flows into the system during the reaction. The position of the piston is also monitored, and it is determined from this data that the piston does 129. kJ of work on the system during the reaction. cylinder water bath gases Is the reaction exothermic or endothermic? O exothermic O 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 absorb Does the reaction absorb or release energy? O release O neither How much energy does the reaction absorb or release? Be sure your answer has the correct number of significant digits.

O THERMOCHEMISTRY Understanding the definitions of heat and work ARL 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 The temperature of the water bath is monitored, and it is determined from this data that 169. kJ of heat flows into the system during the reaction. The position of the piston is also monitored, and it is determined from this data that the piston does 129. kJ of work on the system during the reaction. cylinder water bath gases Is the reaction exothermic or endothermic? O exothermic O 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 absorb Does the reaction absorb or release energy? O release O neither How much energy does the reaction absorb or release? Be sure your answer has the correct number of significant digits.

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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