Heat-loss corrections for small isoperibol-calorimeter reaction vessels

A more exact method of calculating the heat loss from isoperibol-calorimeter reaction vessels is described. This method involves corrections for changes in the heat-leak constant and the external power input with changes in the calorimeter contents, and is particularly important for reaction vessels with volumes of less than 25 cm3 or with heat-leak constants greater than about 0.005 min−1. The new calculation has been tested by application to results collected with a titration calorimeter of capacity 3 cm3.