NISCAIR Online Periodicals Repository

NISCAIR ONLINE PERIODICALS REPOSITORY (NOPR)  >
NISCAIR PUBLICATIONS >
Research Journals >
Indian Journal of Chemistry -Section A (IJC-A) >
IJC-A Vol.46A [2007] >
IJC-A Vol.46A(06) [June 2007] >


Title: Low-temperature heat capacity and standard molar enthalpy of formation of crystalline (S)–(+)–Ibuprofen (C₁₃H₁₈O₂)(s)
Authors: Di, You-Ying
Ye, Chun-Tian
Tan, Zhi-Cheng
Zhang, Guo-Ding
Issue Date: Jun-2007
Publisher: CSIR
Abstract: Low-temperature heat capacities of the compound,(S)–(+)–Ibuprofen (C₁₃H₁₈O₂), have been measured by a precision automated adiabatic calorimeter in the temperature range 78 – 348 K. The experimental molar heat capacities in the temperature range 78 – 345 K have been fitted to a polynomial equation. The smoothed heat capacities and thermodynamic functions, (HT - H₂₉₈․₁₅ĸ) and (ST - S₂₉₈․₁₅ĸ), of the compound have been calculated by the heat-capacity polynomial equation. The constant-volume energy of combustion of the compound, has been found to be ΔUc (C₁₃H₁₈O₂, s) = – (7136.94 ± 4.74) kJmol⁻¹ by means of a home-made oxygen-bomb combustion calorimeter at T = 298.15 ± 0.001 K. The standard molar enthalpy of combustion of the sample has been calculated to be ΔcHmº (C₁₃H₁₈O₂, s) = – (7145.62 ± 4.74) kJmol⁻¹, from the constant-volume combustion energy. The standard molar enthalpy of formation of the compound has been derived, ΔքHmº (C₁₃H₁₈O₂, s) = – (542.48 ± 5.05) kJmol⁻¹, from the combination of the data of standard molar enthalpy of combustion of the compound with other auxiliary thermodynamic quantities through a Hess thermochemical cycle.
Page(s): 947-951
ISSN: 0376-4710
Source:IJC-A Vol.46A(06) [June 2007]

Files in This Item:

File Description SizeFormat
IJCA 46A(6) (2007) 947-951.pdf173.12 kBAdobe PDFView/Open
 Current Page Visits: 769 
Recommend this item

 

National Knowledge Resources Consortium |  NISCAIR Website |  Contact us |  Feedback

Disclaimer: NISCAIR assumes no responsibility for the statements and opinions advanced by contributors. The editorial staff in its work of examining papers received for publication is helped, in an honorary capacity, by many distinguished engineers and scientists.

CC License Except where otherwise noted, the Articles on this site are licensed under Creative Commons License: CC Attribution-Noncommercial-No Derivative Works 2.5 India

Copyright © 2012 The Council of Scientific and Industrial Research, New Delhi. All rights reserved.

Powered by DSpace Copyright © 2002-2007 MIT and Hewlett-Packard | Compliant to OAI-PMH V 2.0

Home Page Total Visits: 559765 since 06-Feb-2009  Last updated on 30-Jul-2014Webmaster: nopr@niscair.res.in