Comparison of Electrocalorimetric and Cooling Methods to Determine Specific Heat of Aqueous Solutions of the Sodium Salt Carboxymethylcellulose

摘要

This article includes the results of experimental research, determining specific heat of water, glycerin, rapeseed oil and aqueous solutions of carboxymethylcellulose sodium salt. Two research methods were used during measurements. The first one uses Newton’s law of cooling. The second one uses electrocalorimetric measurements. The average calculated values of determined parameter for model liquids did not exceed 1% error in cooling method and did not exceed 2% error in calorimetric method. Good conformity of both methods enabled to use them in measurements of liquids with unknown values of specific heat C. In case of carboxymethylcellulose sodium salt, together with increasing concentration, specific heat increases. Significant impact on obtained results has also molar mass M. The highest values C, were obtained for carboxymethylcellulose sodium salt with a molar mass 700,000 kg/kmol and concentration 0.005 kg p/kg within the range of temperatures (303-325) K. Obtained result was over 19% higher than water.