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Homework Help: Entropy change

  1. Feb 13, 2007 #1
    1. The problem statement, all variables and given/known data
    Calculate the changes in total entropy of the universe as a result of the following processes:
    (a) A block of mass 6kg and heat capacity of 300 J/K/kg at 150oC is placed in a lake at 0oC.

    2. Relevant equations

    3. The attempt at a solution
    I think I have found the entropy change of the block as -788 J/K. I am not sure how to find the entropy change of the lake though as I don't know the mass.
    Thanks for any help.
  2. jcsd
  3. Feb 14, 2007 #2
    The change should be equal but opposite. Heat is leaving the block and going into the water... What leave the block must enter the water...
  4. Feb 14, 2007 #3
    yes the energy transfer will be the same but not the entropy.??
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