When can you define temperatures for the molecular energy storage modes (i.e. translational, rotational, vibrational)? I have seen the graphs of this where translational modes are at room temperature and then as temperature increases, the rotational and later vibrational modes are "activated." What assumptions are inherent in this sort of analysis (ideal gas? relationships between Cv and Cp?)..... Thanks for any insight into this! I am starting a course on combustion and am trying to familiarize myself with some background on gas dynamics, etc.