The gas inside the glass container is heated by an electric heater that is turned on for a short time. The temperature increase leads to a pressure increase that is measured by a pressure gauge. In isobaric conditions a temperature increase leads to a volumetric expansion, which can be evaluated with a gas syringe. The molar heat capacities at constant pressure and volume Cv and Cp can be calculated from changes in pressure and volume.
THEORETICAL – EXPERIMENTAL HANDBOOK