An Isoperibolic Micro-Bomb Combustion Calorimeter of Low Cost for Measurement of the Enthalpy of Combustion: Chemical Calibration

A micro static-bomb combustion calorimeter has been developed in our laboratory designing one small cell to obtain combustion heats, which requires only a smaller sample quantity. The energy equivalent of the combustion system has been provided with a new micro-bomb. In the best conditions of operation, the energy equivalent of this calorimetric arrangement is just ε(calor)= (1,1679 ± 0,0004) kJK-1, which means an uncertainty of 0,03% for the calibration with benzoic acid NIST 39 Joule. This combustion calorimeter has been used in the measurement of the enthalpy of combustion of m-methoxybenzoic acid and salicylic acid, giving (-24,21876 ± 0,00102) kJg-1 and (-21,0078 ± 0,0025) kJg-1, respectively, for these substances.