The average kinetic energy of an idealgas atom or molecule is 3/2 kT, where T is the Kelvin temperature (Chapter 18). The rotational inertia of the H₂ molecule is 4.6 × 10^-48 kg ∙ m². What is the value of T for which 3/2 kT equals the energy separation between the l = 0 and l = 1 energy levels of H₂? What does this tell you about the number of H₂ molecules in the l = 1 level at room temperature?