Instrumentation and calibration of the Calvet calorimeter Enthalpy of solution of PrBr₃ at standard conditions

摘要

The original Calvet calorimeter, made from aluminum block, were instrumented. The cells for the solution calorimetry measurement have been projected and constructed. The calibration of calorimeter was performed by measurement of the dependence of reference material on temperature and the influence of mechanical events on thermograms. The enthalpies of solution in water and 0.01 M HCl were investigated for chlorides and bromides of alkali metals (Na···Cs), PrBr₃ and Rb₃PrBr₆. The enthalpies of solution of alkali halides have been compared to the reference data obtained for infinite solution. The decomposition of Rb₃PrBr₆ at temperatures lower than 399 K has been stated. The enthalpy of solution PrBr₃ at 298.15 K has been determined.