Background: it is a Calorimetry lab. We used styrofoam cups as calorimeters, we
ID: 583062 • Letter: B
Question
Background: it is a Calorimetry lab. We used styrofoam cups as calorimeters, we ran a trial with water to determine the calorimeter constant. Following that we did the actual experiement with HCl + NaOH and Acetic Acid + NaOH
I predict the calorimeter constant and energy absorbed by the calorimeter constant would be off.
------------------------------
Thermometer Calibration 1. Reading on Thermometer 1 (C) 17.2 2. Reading on Thermometer 2 (C) 20.9 [3] Correction to be applied to Thermometer 2 (C) 3.7 Note: thermometer 1 will be used in Calorimeter Determination of Calorimeter Constant 4. Temperature of 50.0mL of cool water in calorimeter immediately before hot water is added (C) 17.5 5. Temperature of 50.0mL of hot water immediately before adding it to calorimeter (C) 52.8 [6] Temperature at mixing from excel graph (C) 31.953 [7] Temperature change of cool water, T (C) 14.4 [8] Temperature change of hot water, T (C) -20.9 [9] Heat gained by cool water (J) 3012.48 [10] Heat lost by hot water (J) 4372.28 [11] Difference in Energy (J) 1359.8 [12] Calorimeter Constant (J/C) 94.4 Determination of Calorimeter Constant HCl Trial Acetic Acid Trial 13. Temperature of 50.0mL of Acid in calorimeter immediately before adding NaOH (C) 21.0 21.0 14. Temperature of 50.0mL of NaOH immediately before adding it to calorimeter (C) 21.0 20.5 [15] Temperature at mixing from excel graph (C) 42.1 40.2 [16] Energy absorbed by the solutions (J) 4410 4410 [17] Energy absorbed by the Calorimeter (J) 4410 4120 [18] Total energy produced by neutralization (J) 8820 8530 [19] Molar heat of neutralization (KJ/mol) 58.8 56.9 2) If a student's coffee cups are discarded after the first HCl reaction and new coffee cups are used only for the final reaction with acetic acid. How would this error impact the results?Explanation / Answer
a) In the coffee cup calorimeter experiment, discarding the coffee cup after the initial run of HCl and using fresh cups for the final runs would induce an error in the reacdings. The coffee cup employed for HCl run is used to determine the calorimetry constant and using new cups which may have a different calorimetry constant wold change the calculated value for molar heat of neutralization estimated in the experiment. It is thus very important to use the same cup for which the calorimetric constant has been determined.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.