Abstract
Techniques for determining the enthalpies of sublimation of low volatile
materials in the vapor phase are quite rare. Although benzoic acid,
ferrocene, and naphthalene are used as reference materials for indirect
determination of vapor pressure of volatile materials, the discrepancy
of the values of their enthalpies of sublimation is considerably large
(similar to 10-15 kJ/mol). In this work, the enthalpies of sublimation
of vapors of these materials are determined using absorbance
spectroscopy in the ultraviolet region of the electromagnetic spectrum.
This methodology is based on the linear proportionality between the
density of the saturated gas of the material and the absorbance of the
gas. The determined values of enthalpies of sublimation are in excellent
agreement with the mean value of those reported in literature and those
recommended by the ICTAC. This method is shown to be accurate and rapid.
(C) 2013 Elsevier B.V. All rights reserved.
Original language | English |
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Pages (from-to) | 228-231 |
Journal | Chemical Physics |
State | Published - Mar 2013 |