
Exeriment A: Heat Capacity Ratios
Writeup Format: Short Lab Format
Helpful readings: Engel and Reid, Thermodynamics, Statistical Thermodynamics and Kinetics (1e) ``Equipartition Theorem'' (page 345) and
``Heat capacities'' (section 15.3, pg 362366).
 Calculate gamma for each gas. Report this value with
uncertainties.
 Compare gamma with the theoretical gamma
for an ideal gas. As N_{2} is a diatomic gas:
 Calculate theoretical gamma assuming that
rotational modes are fully excited and that vibrational
modes do not contribute at all.
 Calculate theoretical gamma assuming that
rotational modes are fully excited, this time considering that
vibrational modes may contribute. To do this, you will
need to calculate C_{v}(vib) from the vibrational frequencies
for the molecule in question. (see Engel and Reid, Thermodynamics...., p. 364, eqn 15.41).
Vibrational frequencies can be obtained from the NIST web site.
(see pchem links). Comment on the magnitude of the deviation of this gamma from the one calculated assuming vibrational
modes do not contribute at all.
 Discuss any significant deviations of your experimental values
from theoretical values.
 To convert pressures from mm dibutylphthalate (d = 1.047 g/ml) to mm Hg (d = 13.594 g/ml). This is a straight ratio. Suppose my manometer reading are LOW side = 32.1 cm dibutylphthalate and HIGH side = 74.8 cm dibutylphthalate, and the barometer reading for the day was 722.1 mm Hg.
The pressure difference between the atmospheric pressure and the bottle is:
P_{diff} = 74.8 cm  32.1 cm = 42.7 cm dibutylphthalate (dbp, for now)
or in millimeters: 427 mm dbp
Converting to mm Hg:
1.047 g dbp 1 cm^{3} Hg
P_{diff} = (427 mm dbp) x  x  = 32.9 mm Hg
1 cm^{3} dbp 13.594 g Hg
P_{tot} = P_{atm} + P_{diff} = 722.1 mm Hg + 32.9 mm Hg= 755 mm Hg = 755 torr.
Exeriment B: Langmuir Adsorption
Writeup Format: Formal Format
Helpful readings: Engel and Reid, Thermodynamics, Statistical Thermodynamics and Kinetics (1e) ``Homogeneous and Heterogeneous Catalysis'' (sections 19.4.5, pages 498503).
 Use Excel to perform your calculations
 Graph your data for the Freundlich and Langmuir Adsorption isotherms
 Report your values for the Freundlich and Langmuir parameters
 Report the surface area, of the charcoal, S.
 Discuss whether or not the data are accurately described by each the isotherms.
 Comment on the validity and possible problems with each model
 Comment on your surface area results
Exeriment C: UV/Vis Spectroscopy
Writeup Format: Formal Report Format
Helpful readings: Engel, Quantum Mechanics and Spectroscopy (1e) ``The Particle in a OneDimentional Box'' (section 4.2, pages 4651), ``Solving the Schrodinger Equation in Two Dimensions'' (section 7.2, pages 108111) and sections 15.515.7 (pages 308313) from the ``Electronic Spectroscopy'' Chapter.
 Calculations are described in the laboratory handout. You will need to use CAChe to complete this assignment.
Exeriment D: Resonance Energy of Benzene
Writeup format: Short Format.
Helpful readings: Engel, Quantum Mechanics and Spectroscopy (1e) See ``Huckel Rules'' and ``Resonance Stabilization Energy'' in Section 14.7 (see pages 293296), and consult your organic text.
 Calculations and questions to answer are described at the end of the laboratory handout. You will need to use CAChe to complete this assignment.
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Questions should be directed to Dr. Kimberly LawlerSagarin: ksagarin@elmhurst.edu
