When a solid dissolves in water, the solution may become hotter or colder. The dissolution enthalpy (dissolving) can be determined using a coffee cup calorimeter. In the laboratory a general chemistry student finds that when 21.17 g BaBr2(s) is dissolved in 113.40 g water, the temperature of the solution increases from 24.37 to 27.48 °C. The heat capacity of the calorimeter (sometimes referred to as the calorimeter constant) was determined in a separate experiment to be 1.54 J/ºC. Based on the student's observation, calculate the dissolution enthalpy of BaBr2(s) in kJ/mol. Assume the specific heat capacity of the solution is equal to the specific heat capacity of water. AdisH kJ/mol

When a solid dissolves in water, the solution may become hotter or colder. The dissolution enthalpy (dissolving) can be determined using a coffee cup calorimeter. In the laboratory a general chemistry student finds that when 21.17 g BaBr2(s) is dissolved in 113.40 g water, the temperature of the solution increases from 24.37 to 27.48 °C. The heat capacity of the calorimeter (sometimes referred to as the calorimeter constant) was determined in a separate experiment to be 1.54 J/ºC. Based on the student's observation, calculate the dissolution enthalpy of BaBr2(s) in kJ/mol. Assume the specific heat capacity of the solution is equal to the specific heat capacity of water. AdisH kJ/mol

Chemistry: The Molecular Science

5th Edition

ISBN:9781285199047

Author:John W. Moore, Conrad L. Stanitski

Publisher:John W. Moore, Conrad L. Stanitski

Chapter4: Energy And Chemical Reactions

Section4.8: Measuring Reaction Enthalpies: Calorimetry

Problem 4.17E

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