Calorimetry: Heat of Reaction CHEM 131L Post Lab Assignment help

Question description

Include the following information at the top of the first page of your assignment:

Name:
Lab Partner Name: Lab Section Number: Experiment Title: Due Date:

GENERAL INSTRUCTIONS

The entire report should be typed (handwritten portions will NOT be graded). Please organize your report as shown below. You and your lab partner may not work together on the data analysis, or turn in the same work or answers to questions. If you need help with calculations, you may ask for help from your instructor or the tutoring center.

DATA & CALCULATIONS

  1. Part B:
    1. Show typed calculations for the following values: mhot, ∆Thot, qhot, mcool,

      ∆Tcool, qcool, qcal, ∆Tcal, and Ccal.

    2. Create a table of just the calculated values listed above, displaying each value with proper units, mathematical sign and correct number of significant figures.
  2. Part C:
    1. Show one set of typed calculations for the following values: msoln, ∆Tsoln, qsoln, qcal, qneut, mole of the limiting reactant and molar qneut. If you performed multiple trials, only show calculations for one trial.
    2. Create a table of just the calculated values listed above, displaying each value with proper units, mathematical sign and correct number of significant figures. If you performed more than one trial, report the values for all trials in this table, as well as the average molar qneut.

QUESTIONS – All answers should be typed and given in complete sentences unless otherwise indicated.

  1. If some of the hot water evaporated during the heating process in part B, would that cause the calculated value of Ccal to be too large, too small, or unchanged in magnitude? Explain your reasoning.
  2. Write the chemical equation for the reaction in part C and give the molar heat of reaction. Based on the data, is the reaction in part C exothermic or endothermic? Explain your answer. As part of your answer, explicitly state from where and to where the heat flowed during the reaction.
  3. For each of the following components from part C, indicate whether they are part

of the a. b. c. d. e. f.

system or the surroundings. Styrofoam cups Thermometer Hydrochloric acid Sodium hydroxide

Water from the sodium hydroxide solution

Water product from the reaction

4. Give two possible sources for error that might have occurred during part C. Your answer cannot be based on just ‘human’ error (examples: calculation error, not following directions). Instead think about how the experimental set-up might lead to error.

DATA:

Part B:

80 degrees C -hot water

59.3 degrees C -hot and cold water mixed

24.3 degrees C – cold water

45 mL styrofoam cup

80 mL heated beaker

Part C:

.996M HCl

1.10 M NaOH

51 mL NaOH @ 24.6 degrees C

46 mL HCl @25.5 degrees C

NaOH and HCl mixed 31.4 degrees C