Suppose that an unknown mass of X (MW = 56.26) undergoes combustion. The heat from this reaction is then transferred to 146 mL of water, and the water temperature changes from 33.54°C to 83.21°C. Assume the specific heat of water is 4.2 J/(g.°C) and the density of water is 1.0 g/mL. If the enthalpy of combustion of X is -180.82 kJ/mol, how many grams of X had to have reacted? Report your answer to three decimal places.

Suppose that an unknown mass of X (MW = 56.26) undergoes combustion. The heat from this reaction is then transferred to 146 mL of water, and the water temperature changes from 33.54°C to 83.21°C. Assume the specific heat of water is 4.2 J/(g.°C) and the density of water is 1.0 g/mL. If the enthalpy of combustion of X is -180.82 kJ/mol, how many grams of X had to have reacted? Report your answer to three decimal places.

Chemistry

9th Edition

ISBN:9781133611097

Author:Steven S. Zumdahl

Publisher:Steven S. Zumdahl

Chapter6: Thermochemistry

Section: Chapter Questions

Problem 104AE

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