Fatores de Boltzmann e Calor

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The Boltzmann Factor and Partition Functions 93 To calculate the fraction of atoms in each electronic state, we multiply the state's degeneracy by and divide by the summation above. (Note: = 0.69509 cm⁻¹.) State Fraction of atoms, 1000 K Fraction of atoms, 2500 K 1 1.000 0.9998 2 2.545 X 10⁻¹¹ 5.784 X 10⁻⁵ 3 4.966 X 10⁻¹¹ 1.145 X 10⁻⁴ 4 8.273 X 10⁻¹⁷ 3.690 X 10⁻⁷ 3-42. The vibrational frequency of NaCl(g) is 159.23 cm⁻¹. Calculate the molar heat capacity of at 1000 K. (See Equation 3.27.) = 159.23 cm⁻¹, so = 0.22909, and 3-43. The energies and degeneracies of the two lowest electronic states of atomic iodine are listed below. Energy/cm⁻¹ Degeneracy 0 4 7603.2 2 What temperature is required so that 2% of the atoms are in the excited state? As in Problem 3-41, we have (3.44) For 2% of the atoms to be in the excited state, we can substitute into the expression above and write 0.02 = exp -7603.2 -7603.2 0.04 -7603.2 In 0.98 = 0.695097 T = 3420 K =