کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
6660628 | 1426232 | 2015 | 7 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Enthalpies of dissolution of long chain-length alkyltrimethylammonium bromide salts in water at temperatures from 278.15 to 308.15Â K
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
مهندسی شیمی
مهندسی شیمی (عمومی)
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
Molar enthalpies of dissolution, ÎslnHm, of decyl-, dodecyl-, tetradecyl- and hexadecyl-trimethylammonium bromide salts (RMe3NBr) in water have been measured calorimetrically as a function of concentration and temperature. Standard state values, ÎslnHmo, were obtained by extrapolation to infinite dilution and showed a smooth variation with the number of carbon atoms, nC, in the alkyl chain R, unlike their shorter congeners (nC ⩽ 6). The corresponding molar isobaric heat capacity changes, ÎslnCp,mo, were calculated from the temperature dependence of ÎslnHmo and also varied smoothly with nC but were more than an order of magnitude greater than those of their shorter congeners, probably reflecting a marked increase in hydrophobicity with increasing nC. The behaviour of the RMe3NBr salts was found to parallel broadly that of the symmetrical tetraalkylammonium salts, R4NBr.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: The Journal of Chemical Thermodynamics - Volume 81, February 2015, Pages 109-115
Journal: The Journal of Chemical Thermodynamics - Volume 81, February 2015, Pages 109-115
نویسندگان
Diana C. Riveros, Edgar F. Vargas, Glenn Hefter,