Model of Batch Calorimetry Experiment

The model of dilution experiment is depicted in Fig. 6.19. Prior to injection sequence, there is grams of pure solvent in the calorimetric cell. Then, small aliquots of the stock solution of molality are injected by the syringe pump operating at a constant flow rate dpump- When the time of injection tinj is maintained constant, the amount of the solute n introduced into the calorimetric cell is always the same. As a result, the equilibrium solution in the cell becomes more and more concentrated, i.e., m. The dilution data may be further processed in two 

The total enthalpy change during the ith injection per mole of the solute is expressed as follows [73, 74, 88]  

The equilibrium molality of the solution in the cell after this injection is calculated by means of the following expression  

values of /t2 may be obtained experimentally by measuring both enthalpy changes Hi and very small quantities of the solute injected during successive 

The thermal effects of successive injections can be also summed up to obtain the molar cumulative enthalpy of dilution Aduhcum-After k injections, one obtains  

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