I found the field of Biochemistry & Molecular Biology; Chemistry very interesting. Saw the article Calculation of the Isobaric Heat Capacities of the Liquid and Solid Phase of Organic Compounds at and around 298.15 K Based on Their True Molecular Volume published in 2019. Quality Control of Pyrazine-2-carboxylic acid, Reprint Addresses Naef, R (corresponding author), Univ Basel, Dept Chem, CH-4003 Basel, Switzerland.. The CAS is 98-97-5. Through research, I have a further understanding and discovery of Pyrazine-2-carboxylic acid
A universally applicable method for the prediction of the isobaric heat capacities of the liquid and solid phase of molecules at 298.15 K is presented, derived from their true volume. The molecules’ true volume in A(3) is calculated on the basis of their geometry-optimized structure and the Van-der-Waals radii of their constituting atoms by means of a fast numerical algorithm. Good linear correlations of the true volume of a large number of compounds encompassing all classes and sizes with their experimental liquid and solid heat capacities over a large range have been found, although noticeably distorted by intermolecular hydrogen-bond effects. To account for these effects, the total amount of 1303 compounds with known experimental liquid heat capacities has been subdivided into three subsets consisting of 1102 hydroxy-group-free compounds, 164 monoalcohols/monoacids, and 36 polyalcohols/polyacids. The standard deviations for Cp(liq,298) were 20.7 J/mol/K for the OH-free compunds, 22.91 J/mol/K for the monoalcohols/monoacids and 16.03 J/mol/K for the polyols/polyacids. Analogously, 797 compounds with known solid heat capacities have been separated into a subset of 555 OH-free compounds, 123 monoalcohols/monoacids and 119 polyols/polyacids. The standard deviations for Cp(sol,298) were calculated to 23.14 J/mol/K for the first, 21.62 J/mol/K for the second, and 19.75 J/mol/K for the last subset. A discussion of structural and intermolecular effects influencing the heat capacities as well as of some special classes, in particular hydrocarbons, ionic liquids, siloxanes and metallocenes, has been given. In addition, the present method has successfully been extended to enable the prediction of the temperature dependence of the solid and liquid heat capacities in the range between 250 and 350 K.
Quality Control of Pyrazine-2-carboxylic acid. Bye, fridends, I hope you can learn more about C5H4N2O2, If you have any questions, you can browse other blog as well. See you lster.
Reference:
Patent; Chevron Research Company; US4732894; (1988); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem