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Explore the energy levels used to describe the translational part of molecular motion in an ideal gas system within a cubic container of length a. Learn how to compute the total molecular partition function by combining individual partition functions. See the derivation of the translational partition function with contributions from different dimensions.
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Assume that we have an ideal gas, i.e., non-interacting particles, in a cubic container of length a. What are the energy levels that we will use to describe the translational part of the molecular motion? (A) in each dimension (B) in each dimension (C) in each dimension (D) in each dimension
Assume that we have an ideal gas, i.e., non-interacting particles, in a cubic container of length a. What are the energy levels that we will use to describe the translational part of the molecular motion? (A) in each dimension; CORRECT! The PIB with independent motion in x-,y- and z-directions, measured relative to the ground state (B) in each dimension remember that we set the ground state energy to zero! (C) in each dimension There are no forces acting inside the container... no force constant, no H.Osc.! (D) in each dimension see (C) and (B)
If the energy of a molecule comes from several independent • contributions, we can express the total molecular partition • function as ... • ... the sum of the individual partitions: • qtotal = Sk qk • (B) ... linear combinations of the individual partition functions: • qtotal= Sk ck qk • (C) ... the product of the individual partition functions. • qtotal = Pk qk
If the energy of a molecule comes from several independent • contributions, we can express the total molecular partition • function as ... • ... the sum of the individual partitions: • qtotal = Sk qk • (B) ... linear combinations of the individual partition functions: • qtotal= Sk ck qk • (C) ... the product of the individual partition functions. • qtotal = Pk qk • CORRECT! See derivation of translational partition function • with product from different dimensions