One equation for calculating this quantity is only valid when the volume divided by the particle number times the thermal wavelength cubed is greater than 1 and is named for Sackur and Tetrode.
One equation for calculating this quantity is only valid when the volume divided by the particle number times the thermal wavelength cubed is greater than 1 and is named for Sackur and Tetrode. For a gas undergoing a temperature change this quantity is equal to the number of moles, times the heat capacity, times the natural log of final temperature over initial. This quantity is equal to the amount of heat added to a system divided by the system's temperature. It is also equal to Boltzmann's constant times the natural log of the number of microstates. This quantity is always increasing for an isolated system according to the second law of thermodynamics. For 10 points, name this quantity, a measure of the disorder of a system. 
One equation for calculating this quantity is only valid when the volume divided by the particle number times the thermal wavelength cubed is greater than 1 and is named for Sackur and Tetrode.
entropy