Consider a two-level system at thermal equilibrium. The ratios of the excited state population to the ground state population are 0.50 and 0.25 at 600K and 300K, respectively. The energy gap between the two levels (in unit of 10-21 J) is closest to [kB = 1.38 × 10-23JK -1]
1
1.44
2
2.87
3
5.74
4
11.48