contribution to chem
Heat of Neutralization
Introduction:
The purpose of this experiment was to measure, using a calorimeter, the energy changes accompanying neutralization reactions. In order to measure the amount of heat produced by a reaction, an instrument called a calorimeter was used. The calorimeter used in this experiment was somewhat rudimentary. It was constructed as shown in the following picture:
After finding the heat capacity of the calorimeter, the student and partner neutralized two acids and calculated the heat of neutralization. Those two acids were hydrochloric acid and acetic acid, a 1.0 M solution of each was used.
Observation and Results:
The Heat gained by calorimeter = 355.3 J and the heat capacity of calorimeter = 28.9 J/K. For the heat of neutralization of HCl-NaOH the heat gained by the solution was 2508 J whereas the heat gained by the calorimeter was 173.4 J. Therefore the number of joules released per mole of water formed was 47.6. Kj/mol. In the heat of neutralization of HC2H3O2-NaOH, the heat gained by the solution was 2549.8 J, and the heat gained by the calorimeter was 176.3 J. The number of joules released per mole of water formed = 47.4 kJ/mol. The total number of joules released in reaction B (2384.6 J) was more than those released in reaction B (2372.7 J) a difference of 11.9 J.
Discussion:
There were mistakes with equipment and the overall procedure. The measuring devices could account for some of the errors. A graduated cylinder was used to measure volume, but s buret or pipet provides better accuracy. Using a graduated cylinder leaves room for a crucial error in volume determination, which would then lead to errors in determination of mass, molar content of the solution etc. This means that an inaccurate amount of solution may have been poured into the cylinder, but not all of the solution may have been poured out. Some extra drops of solution could have been left clinging to the walls of the cylinder. This would have negatively
Introduction:
The purpose of this experiment was to measure, using a calorimeter, the energy changes accompanying neutralization reactions. In order to measure the amount of heat produced by a reaction, an instrument called a calorimeter was used. The calorimeter used in this experiment was somewhat rudimentary. It was constructed as shown in the following picture:
After finding the heat capacity of the calorimeter, the student and partner neutralized two acids and calculated the heat of neutralization. Those two acids were hydrochloric acid and acetic acid, a 1.0 M solution of each was used.
Observation and Results:
The Heat gained by calorimeter = 355.3 J and the heat capacity of calorimeter = 28.9 J/K. For the heat of neutralization of HCl-NaOH the heat gained by the solution was 2508 J whereas the heat gained by the calorimeter was 173.4 J. Therefore the number of joules released per mole of water formed was 47.6. Kj/mol. In the heat of neutralization of HC2H3O2-NaOH, the heat gained by the solution was 2549.8 J, and the heat gained by the calorimeter was 176.3 J. The number of joules released per mole of water formed = 47.4 kJ/mol. The total number of joules released in reaction B (2384.6 J) was more than those released in reaction B (2372.7 J) a difference of 11.9 J.
Discussion:
There were mistakes with equipment and the overall procedure. The measuring devices could account for some of the errors. A graduated cylinder was used to measure volume, but s buret or pipet provides better accuracy. Using a graduated cylinder leaves room for a crucial error in volume determination, which would then lead to errors in determination of mass, molar content of the solution etc. This means that an inaccurate amount of solution may have been poured into the cylinder, but not all of the solution may have been poured out. Some extra drops of solution could have been left clinging to the walls of the cylinder. This would have negatively