Low-temperature heat capacity C-p.m of 2-amino-5-nitropyridine (C5H5N3O2; CAS 4214-76-0) was measured in the temperature range from 80 to 396 K with a high precision automated adiabatic calorimeter. No phase transition or thermal anomaly was observed in this range. The thermodynamic functions [HT - H298.1-5] and [S-T - S-298.15] were calculated in the range from 80 to 395 K based on the heat capacity data. The standard molar energy and standard molar enthalpy of combustion have been determined, Delta U-c (C5H5N3O2, s) = -(2676.26 +/- 0.24) U mol(-1) and Delta H-c(m)degrees (C5H5N3O2, s) = -(2673.16 +/- 0.24) U mol(-1), by means of a precision oxygen-bomb combustion calorimeter at T= 298.15 +/- 0.001 K. The standard molar enthalpy of formation has been derived, Delta H-f(m)degrees, (C5H5N3O2, s) = -(8.97 +/- 0.99) kJ mol(-1), from the standard molar enthalpy of combustion in combination with other auxiliary thermodynamic quantities through a Hess thermochemical cycle. The thermodynamic properties were further investigated through differential scanning calorimeter (DSC) and the thermogravimetric (TG) analysis. (C) 2007 Elsevier B.V. All rights reserved.