Entropy Change of Universe: 6kg Block & Lake

swain1
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Homework Statement


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.

Homework Equations


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.
 
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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...
 
yes the energy transfer will be the same but not the entropy.??
 

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