In this work, using a differential scanning calorimeter, I tried to measure the temperature
dependence of the specific heat capacities of 2 M aqueous solutions of mixed NaBr and
KF salts, in which I changed the ratio between the two electrolytes, while the total salt
concentration always remained equal to 2 mol/dm3. As a reference liquid for these
measurements, I used very pure water (type 1), prepared with an ion exchanger. I made
measurements in the range between 5 °C and 60 °C with a Nano DSC differential
scanning calorimeter from TA Instruments. A very important part of this task was to
determine the error that accompanies the determination of these specific heat capacities
and, if possible, to discover how to reduce this error as much as possible. The
thermograms obtained during these experiments were burdened with considerable signal
fluctuation in the higher temperature range, which I noticed only after I recorded all the
thermograms. The cause of this fluctuation, which is not present during normal operation
of the instrument, is most likely the intrusion of air from the surroundings into the
evacuated space surrounding the measuring cell. If I wanted to fully fulfill the assigned
task within the framework of this diploma work, it would first be necessary to re-establish
the vacuum around the cells and then repeat the experiments in their entirety.
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