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 600 K and 300 K, respectively. The energy gap between the two levels (in unit of 10–21J) is closest to

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The system with the largest internal pressure is

A compound consists of atoms A and B. Atoms of B form cubic close packing lattice and atoms of A occupy half of octahedral voids and half of tetrahedral voids. What is the molecular formula of the compound?

Entropy associated with a die with all its six faces having equal probability of being on top is (k_B : Boltzmann constant):

​$$\text{The characters of a reducible representation } \Gamma_R \text{ under the } C_{3h} \text{ point group are presented at the end of the character table below. The correct coefficients of the irreducible representations } A' \text{ and } A'' \text{ in the } \Gamma_R \text{ are}$$​

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The equivalent symmetry operations for $$S^4_6$$ and $$S_3^3$$ are, respectively,​

The system with the largest internal pressure is

A compound consists of atoms A and B. Atoms of B form cubic close packing lattice and atoms of A occupy half of octahedral voids and half of tetrahedral voids. What is the molecular formula of the compound?

Entropy associated with a die with all its six faces having equal probability of being on top is (k_B : Boltzmann constant):

​$$\text{The characters of a reducible representation } \Gamma_R \text{ under the } C_{3h} \text{ point group are presented at the end of the character table below. The correct coefficients of the irreducible representations } A' \text{ and } A'' \text{ in the } \Gamma_R \text{ are}$$​

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The equivalent symmetry operations for $$S^4_6$$ and $$S_3^3$$ are, respectively,​