In this article the construction of a simple calorimeter (with easily acquired materials) for the determination of the enthalpy of neutralization at constant pressure of acid-base reactions is described. Solutions of weak and strong acids and bases, one thermometer, and one expanded-polystyrene (Styrofoam) container were used in the development of the experiment. With this calorimeter, it was possible to determine the enthalpy of neutralization of reactions and compare the obtained values with the most accepted one of - 55.84 kJ mol-1, at 25 ° C [1].
enthalpy of neutralization; calorimetry; calculation of enthalpy of neutralization