1. The problem statement, all variables and given/known data One litre cylinder contains 1 mole of the ideal gas molecules having the average kinetic energy of 0.1eV. What is the total energy of this gas? 2. Relevant equations W = K + U 3. The attempt at a solution I figured because the cylinder is closed, no stated temperature change, or volume/pressure change, there is no work? So U=-K K = 0.1eV = 1.6 x10-20J. Therefore, U = -1.6x10-20 J. Is this line of thinking correct? Can it really be that simple..