The purpose of the Gases laboratory is to demonstrate the behavior of ideal, real, and van der Waals gases under varying experimental conditions. The principles governing the behavior of gases, together with the mathematical relationships describing this behavior, are important concepts that are relevant in many fields of chemistry and physics. As in all of the virtual labs, the main focus of the Gases laboratory is to allow students the ability to explore and discover, in a safe and level-appropriate setting, the concepts and ideas that are important in the study of gas properties.
The gas experiments included in the simulated laboratory allow students to explore and better understand the behavior of ideal gases, real gases, and van der Waals gases (a model real gas). The gases laboratory contains four experiments each of which includes the four variables used to describe a gas: pressure (P), temperature (T), volume (V), and the number of moles (n). The four experiments differ by allowing one of these variables to be the dependent variable while the others are independent. The four experiments include (1) V as a function of P, T, and n using a balloon to reflect the volume changes; (2) P as a function of V, T, and n using a motor driven piston; (3) T as a function of P, V, and n again using a motor driven piston; and (4) V as a function of P, T, and n but this time using a frictionless, massless piston to reflect volume changes and using weights to apply pressure. The gases that can be used in these experiments include an ideal gas; a van der Waals gas whose parameters can be changed to represent any real gas; real gases including N2, CO2, CH4, H2O, NH3, and He; and eight ideal gases with different molecular weights that can be added to the experiments to form gas mixtures.