At high temperatures, when the thermal energy k B T is much greater than the spacing hν between energy levels, the exponential argument βhν is much less than one and the average energy becomes k B T, in agreement with the equipartition theorem (Figure 10). However, at low temperatures, when hν ≫ k B T, the average energy goes to zero—the higher-frequency energy levels are "frozen out" (Figure 10). As another example, the internal excited electronic states of a hydrogen atom do not contribute to its specific heat as a gas at room temperature, since the thermal energy k B T (roughly 0.025 eV) is much smaller than the spacing between the lowest and next higher electronic energy levels (roughly 10 eV).