Lab Report Chemistry 1
ahmed1998
Template-Calorimetry.docxUse the following template to write your lab report. Avoid using first person when writing. Lab reports are double-spaced. Follow the Calorimetry experiment lab rubric to check how points are allotted.
Determining the Enthalpy of a Chemical Reaction
Name
Team members
Date
GSA’s name
Section
PROCEDURE (States changes made to the procedure. If no changes were done, say the procedure was followed as written.)
RESULTS FOR PART A (Fill in the data table. Write sample calculations and give a brief analysis of results.)
Table 1: Heat Capacity of Calorimeter #1
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Trial 1 |
Trial 2 |
Trial 3 |
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Initial temperature of room temperature water from temperature probe, Ti (ºC) |
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Mass (g) room temperature water (density = 1.0 g/mL) |
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Initial temperature of warm water from thermometer, Ti (ºC) |
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Mass (g) warm temperature water (density = 1.0 g/mL): |
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Maximum temperature observed over 3 minutes, Tf (ºC) |
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ΔTlost (warm water) (ºC)
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qlost (warm water) (J)
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ΔTgain (room T water) (ºC)
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qgain (room T water) (J)
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qcal (J)
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Ccal (J/oC)
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Average Ccal for calorimeter #1 (J/oC)
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Table 2: Heat Capacity of Calorimeter #2
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Trial 1 |
Trial 2 |
Trial 3 |
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Initial temperature of room temperature water from temperature probe, Ti (ºC) |
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Mass (g) room temperature water (density = 1.0 g/mL) |
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Initial temperature of warm water from thermometer, Ti (ºC) |
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Mass (g) warm temperature water (density = 1.0 g/mL): |
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Maximum temperature observed over 3 minutes, Tf (ºC) |
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ΔTlost (warm water) (ºC)
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qlost (warm water) (J)
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ΔTgain (room T water) (ºC)
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qgain (room T water) (J)
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qcal (J)
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Ccal (J/oC)
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Average Ccal for calorimeter #1 (J/oC)
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Sample calculations: (Write sample calculations done on one of the trials to determine heat capacity of the calorimeter. Define the variables of the equations and include units.)
Analysis of results: (Write a short paragraph where you explain how the calorimeter constants values compare and why this value is needed on Part B.)
RESULTS FOR PART B (Fill in the data table. Write sample calculations and give a brief analysis of results.)
Table 3: Reaction between NaOH and HCl
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Trial 1 – Calorimeter #1 |
Trial 2 – Calorimeter #2 |
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Mass of entire solution, (g). Hint: Assume the density of both solutions = 1.0 g/mL |
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Initial temperature of HCl prior to mixing, Ti (ºC) |
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Tf after mixing (highest or lowest T over 3 minutes) (ºC) |
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ΔT (ºC)
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qsoln (kJ)
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qcal (kJ)
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qrxn (kJ)
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ΔHrxn (kJ)
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Average ΔHrxn (kJ)
Exothermic or Endothermic?
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Table 4: Reaction between NaOH and NH4Cl
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Trial 1 – Calorimeter #1 |
Trial 2 – Calorimeter #2 |
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Mass of entire solution, (g). Hint: Assume the density of both solutions = 1.0 g/mL |
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Initial temperature of NaOH prior to mixing, Ti (ºC) |
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Tf after mixing (highest or lowest T over 3 minutes) (ºC) |
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ΔT (ºC)
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qsoln (kJ)
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qcal (kJ)
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qrxn (kJ)
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ΔHrxn (kJ)
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Average ΔHrxn (kJ)
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Table 5: Reaction between HCl and NH4OH
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Trial 1 – Calorimeter #1 |
Trial 2 – Calorimeter #2 |
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Mass of entire solution, (g). Hint: Assume the density of both solutions = 1.0 g/mL |
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Initial temperature of HCl prior to mixing, Ti (ºC) |
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Tf after mixing (highest or lowest T over 3 minutes) (ºC) |
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ΔT (ºC)
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qsoln (kJ)
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qcal (kJ)
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qrxn (kJ)
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ΔHrxn (kJ)
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Average ΔHrxn (kJ)
Exothermic or Endothermic?
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Using Hess’s Law and your average ΔHrxn for reactions 1 and 2, what would you have expected ΔHrxn to equal |
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Table 6: Heat of Solution for Dissolving Ammonium Nitrate
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Trial 1 – Calorimeter #1 |
Trial 2 – Calorimeter #2 |
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Mass of entire solution, (g) (density = 1.0 g/mL) |
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Initial temperature of water prior to mixing, Ti (ºC) |
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Tf after mixing (highest or lowest T over 3 minutes) (ºC) |
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ΔT (ºC)
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qsoln (kJ)
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qcal (kJ)
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qrxn (kJ)
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ΔHrxn (kJ)
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Average ΔHrxn (kJ) Exothermic or Endothermic?
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Table 7: Heat of Reaction for a Redox Reaction
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Trial 1 – Calorimeter #1 |
Trial 2 – Calorimeter #2 |
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Mass of entire solution, (g) (density = 1.0 g/mL) |
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Initial temperature of HCl prior to mixing, Ti (ºC) |
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Tf after mixing (highest or lowest T over 3 minutes) (ºC) |
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ΔT (ºC)
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qsoln (kJ)
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qcal (kJ)
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qrxn (kJ)
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ΔHrxn (kJ)
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Average ΔHrxn (kJ) Exothermic or Endothermic?
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Sample calculations: (Write sample calculations done on one of the trials for any of the reactions. Also include the calculations for determining Hess’s Law. Define the variables of the equations and include units.)
Analysis of results: (Write a short paragraph where you explain how the reactions compare or contrast between each other and if any trends are observed.). Your answer must follow report guidelines.
DISCUSSION (Answer the following questions correctly and thoroughly using complete sentences.)Your answer must follow report guidelines.
1. Using Hess’s Law, manipulate your ΔHrxn values for reaction 1 and 2 to calculate an expected ΔHrxn value for reaction 3. How does your calculated value compare to your experimental value? Include the calculations and the balanced equations for determining Hess’s Law.(5 pts.)
2. For each of the reactions performed in this experiment, identify each of them as either exothermic or endothermic. (5 pts.)
3. Why do you use a Styrofoam cup calorimeter instead of a glass beaker for these reactions? (5 pts.) (Hint: Compare heat capacities)
4. Write down the balanced equation for reaction between HCl and Mg? What is the gas released in this reaction? (5 pts.)
5. What do you expect to see if you use Mg strips instead of Mg powder? Comment on the similarity and/or differences in the rate and heat of the reaction (5 pts.)
REFLECTION (Explain personal contributions to the experiment as well as the contributions from the members of your team. Identify at least one limitation encountered and give at least one suggestion for improvement.)
