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Temperature combination, Homework (HELP)

  1. Apr 30, 2009 #1
    1. The problem statement, all variables and given/known data[/b]
    Four ice cubes at exactly O degrees C having a total mass of 53.5g are combined with 115 g of water at 75 degrees C in an insulated container. If no heat is lost to the surroundings, what will be the final temperature of the mixture?

    2. Relevant equations[/b]
    q=m x Cs x ^T
    q= n x ^H fus

    Cs ice= 2.09 J/gC
    for H20 ^H fus= 6.02 KJ/mol
    18.02 g=1 mol for H20

    3. The attempt at a solution
    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. May 1, 2009 #2


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    Gold Member

    Use the idea of conservation of energy. The heat energy transferred to the ice blocks will be equal to the heat energy lost by the water.
  4. May 1, 2009 #3
    What about the Heat of fusion for the ice melting?
    I figured it had something to do with finding the energy to melt the ice (the phase change part) plus the energy as the ice goes up to 75 degrees, and then set the combination equal to the mass of the solution x the specific heat of water x the final temp (unknown) - initial temp 75.
    I know that's wrong because the ice doesn't necessarily go to 75 degrees, in fact the temp should be lower. Any suggestions?
  5. May 1, 2009 #4


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    Staff: Mentor

    Try to write equations describing energy balance as danago proposed. Some of your concepts are OK, once you will write it all as an equation it should be obvious.
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