Thermochemical results for “tris” as a test substance in solution calorimetry

Enthalpies of reaction of tris(hydroxymethyl)aminomethane in HCl(aq) and in NaOH(aq)

“…g-l. This equation agrees with the values reported by Hill et al [15], within the uncertainties of the NaOH analyses.…”

“…There is good agreement between the two values re ported ( [15] and sec. 3.4) for the endothermic reaction of the Standard Reference Material in 0.05 N NaOH, and the uncertainty assigned to the certified value is approximately as expected.…”

Calorimetric investigation of complex formation in the aqueous Fe (III)–citrate system

“…We checked the accuracy of our calorimeter by way of test measurements of the enthalpy of solution of KCl(cr) in distilled water, the enthalpy of solution of 4-aminopyridine(cr) in excess aqueous perchloric acid, the enthalpy of solution of THAM(cr) in excess aqueous hydrochloric acid, and the enthalpy of neutralization of THAM(aq) by excess hydrochloric acid. Results of these measurements are in good agreement with "bestn results from the literature (6,(8)(9)(10)(11)(12)(13), as will be discussed elsewhere,' where we also provide a more detailed description of the calorimeter. Another test was provided by calculating the enthalpy of neutralization of OH-(aq) by H+(aq) as described in the fourth paragraph below.…”

Solvation of the proton and the trifluoromethanesulfonate ion in eight solvents

“…A program was written in Basic to process the resistance-time signals of the calorimeter (7). The performance of the calorimeter was checked by determining the solution enthalpy of dried tris(hydroxymethy1)aminomethane (Aldrich) in 0.1 M aqueous HCI at 25.00 and 30.00"C. The values obtained were within 1% from literature data (8). This accuracy, although moderate, was adequate for our purpose.…”