| Autor: |
Kilday MV; Center for Thermodynamics and Molecular Science, National Bureau of Standards, Washington, DC 20234. |
| Jazyk: |
angličtina |
| Zdroj: |
Journal of research of the National Bureau of Standards (1977) [J Res Natl Bur Stand (1977)] 1978 Nov-Dec; Vol. 83 (6), pp. 547-554. |
| DOI: |
10.6028/jres.083.036 |
| Abstrakt: |
An adiabatic solution calorimeter was used to measure enthalpies of solution in water of 7 uracil samples in a concentration range of 3 to 45 mmol · kg -1 and over a temperature range of 298 K to 325 K. Analytical data for the samples are given. Our best value for the enthalpy of solution is Δ H 0 ( ∞ , 298.15 K ) = ( 29.33 ± 1.2 ) kJ mol - 1 and for the change in heat capacity for the reaction with temperature, Δ C p 0 = ( 57 ± 13 ) J mol - 1 K - 1 No change in the enthalpy of solution with concentration was found in this range. Values were calculated for the entropy of solution, Δ S ° = (68.1 ± 4.2) J · mol -1 · K -1 , and for the apparent molal heat capacity at infinite dilution, C p 2 0 = ( 178 ± 15 ) J m o l - 1 K - 1 . |
| Databáze: |
MEDLINE |
| Externí odkaz: |
|
