The objective of this paper is to present a laboratory program designed for the Thermodynamics course offered in the Department of Thermal Engineering at the University of the Basque Country. With reference to one of the examples given in the textbook by Moran, Shapiro, Boettner and Bailey (2012), the balances of mass, energy, entropy and exergy are applied to a particular control volume, and the ideal gas model is used. Using a Ranque-Hilsh vortex tube (Ranque, 1934), the division of a compressed air flow into two streams at a lower pressure is achieved: one hot stream, where the temperature can exceed 100 degrees C, and another cold stream, in which temperatures can fall below -40 degrees C. Therefore, an air flow is divided into two separate hot and cold streams, without any thermal interaction with hot or cold focuses. The vortex tube is used to demonstrate the basics of the First and Second Law of Thermodynamics. In addition, this practical laboratory program can even be used to make sense of one of the best-known theoretical experiments in thermodynamics, the so-called Maxwell's demon experiment (Lewins & Bejan, 1999; Liew, Zeegers, Kuerten & Michalek, 2012). It should also be noted that once a compressed air source has been provided, the material needed to prepare the practicum is simple and affordable, and the lab itself is very interesting and appeals to students.