The dissolution of propan-1-ol and dilution of 10 wt.% propan-1-ol solution in water as calibration and test reactions in solution calorimetry

The enthalpy of solution of propan-1-ol in water is a convenient and reliable calibration and test reaction in titration microcalorimetry. The solution enthalpy varies significantly with concentration; hence, it is usually necessary to make extrapolations to infinitely dilute solution to determine ΔsolHm∞ in order to derive a value suitable for comparison. We outline the thermodynamic formalism for the titration solution experiments and indicate an extrapolation procedure. An experimental example is given. Since less energetic test reactions are often desirable, the dilution of 10 wt.% propan-1-ol solution in water has been suggested as such a reaction. Thus, we have made dilution measurements in order to explore the accuracy of the reported enthalpy value and found that the uncertainty is, at present, at least a couple of percent. Some experimental considerations when performing titration microcalorimetric experiments are discussed.