Lab Experiment 6- Thermodynamic Measurements PDF

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Summary

Lab 5...

Description

1 KCl

3 H2SO4

4 HCl + Mg

(endothermic or exothermic)

Equation for Reaction, including the heat term and state labels

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Experiment 6

5 HCl + NaHCO3

Reaction Class

Data and Results

2 Ca(C2H3O2)2

Tfinal (°C)

Chemistry 134

Reaction

Tinitial (°C)

Part 1. Qualitative Study of Endothermic and Exothermic Reactions

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Table 1. Qualitative Study of Selected Exothermic and Endothermic Reactions.

Chemistry 134

Experiment 6

Part 2. Quantitative Study of the Enthalpy of Fusion of Ice Determination of the Calorimeter Constant Table 2. Determination of Correction Factor for Thermometer. thermometer

Temperature (°C)

Correction factor* (°C)

1 (in calorimeter) 2 *Correction factor, CF = Ttherm1 – Ttherm2 To apply for subsequent measurements: Ttherm2 corrected = Ttherm2 + CF Table 3. Data for Determination of Calorimeter Constant Trial

1

2

Temperature cold H2O (°C) Temperature hot H2O (°C) Highest temp on mixing (°C) 'Tcold (°C) 'Thot (°C) Calculation of Calorimeter Constant (Example provided on page 70.). Show all work. Trial 1.

Trial 2.

Average Value.

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Chemistry 134

Experiment 6

Part 2. Quantitative Study of the Enthalpy of Fusion of Ice (continued) Determination of the Enthalpy of Fusion of Ice Table 4. Masses of ice and water used in the trials. Trial 1

2

Mass H2O (g) Mass apparatus + ice (g) Mass apparatus (g) Mass ice (g) Table 5. Change in Temperature Over Time. (Indicate time of mixing with a .) Trial 2 Trial 1 Temperature (°C) Temperature (°C) Time (s) Time (s)

'T trial 1 (°C)____________ ©University of Michigan-Dearborn

'T trial 2 (°C) _____ ______ 77

Chemistry 134

Experiment 6

Trial 1 Calculate 'Hfus. Show all work.

Trial 2 Calculate 'Hfus. Show all work.

Average value 'Hfus. Show all work.

Relative error(%) 'Hfus. Show all work.

Question 1. Briefly explain why it is necessary to calculate and use a calorimeter constant in a procedure such as this one.

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