Standard partial molar heat capacities and volumes of aqueous N-methylpiperidine and N-methylpiperidinium chloride from 283 K to 393 K

Densities and volumetric heat capacities for dilute solutions of N-methylpiperidine (N-MP, 0.2 mol.kg(-1)) and N-methylpiperidinium chloride (N-MPH+Cl-, 0.1 mol.kg(-1)) were measured relative to water at 0.1 MPa using a vibrating-tube densimeter, and at 0,4 MPa using a twin fixed-cell, power compensation, differential temperature-scanning nano calorimeter, over the temperature ranges 283.15 K <= T <= 363.15 K and 283.15 K <= T <= 393.15 K, respectively. The resulting apparent molar volumes, V-phi, and heat capacities, C-p,C-phi, were corrected for speciation effects using Young's rule and extrapolated to infinite dilution using the Debye-Huckel limiting law, Y-o approximate to Y-phi A(Y)I(s)(1/2), to yield the standard partial molar properties, Y-o, for N-MP(aq) and N-MPH+Cl-(aq). The standard partial molar volumes, V-o, and heat capacities, C-p(o), were represented by a semi-empirical function of solvent density and temperature, Y-o(rho(w),T), the "density" model, which can be used to extrapolate these results, as well as other thermodynamic properties for the ionization of N-methylpiperidine, to higher temperatures. (C) 2017 Elsevier Ltd.