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Homework Help: Heat problem, determine mass of ice cube?

  1. Jun 18, 2011 #1
    My answer is 12.9 grams, and the correct answer is supposed to be 11.9 grams. I cannot figure out why? Note. the answer i got is 12.9, and not 11.06. I know for this situation, the heat absorbed by the ice equals the heat lost by the water and aluminum, and since there is a phase change from a solid to liquid then i need the heat of fusion constant for solid water, which in kcal/kg which is 79.7. Now I am thinking that this is where my mistake is, because temperature remains constant during a phase change. Therefore, I cannot put 16-(-8.7)? I have to write it out into two separate m*c*deltaT's?
     

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    Last edited: Jun 18, 2011
  2. jcsd
  3. Jun 18, 2011 #2

    ehild

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    Yes, you need two separate m*c*deltaT-s for the ice, as c of ice is different from that of water it becomes after melting.

    ehild
     
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