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Homework Help: Entropy of a quantum sized material

  1. Dec 8, 2011 #1
    1. The problem statement, all variables and given/known data
    A small material has quantum oscillator energy levels 2E-23 J apart. Suppose the material has a total energy of 34E-23 J and contains 5 atoms. Find the entropy of the material.

    2. Relevant equations
    Entropy = (Boltzmann's constant)*ln(multiplicity)

    Multiplicity = (q + N - 1)!/[q!(N-1)!]

    3. The attempt at a solution
    I'm having trouble grasping the question. The 5 atoms are understood, but I'm having trouble finding the "N" for the multiplicity equation.

    So, I came up with N = 18, because the total energy is 34E-23 J and the energy levels are 2E-23 J apart, and q = 5.

    Then applying the multiplicity equation and plugging it to entropy, I didn't get the correct answer.

    Am I on the correct path to find N, or do I even need the multiplicity equation?
  2. jcsd
  3. Dec 9, 2011 #2
    Anyone, please?
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