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Homework Help: Thermochemistry and Equilibrium of Reaction

  1. Jun 6, 2009 #1
    1. The problem statement, all variables and given/known data
    An ice cube of mass 36 g at temperature -10 Celsius is placed in 360 g of water at 20 Celsius. Find thermal equilibrium temperature. [tex]\Delta[/tex]H(fusion) = 6.007 kJ mol[tex]\wedge[/tex]-1.

    Molar heat capacity of ice = 38
    water = 75 (Joules)/(K mol)

    Assume no heat loss to the surroundings.
    2. Relevant equations
    [tex]\Delta[/tex] H = n(Cp) [tex]\Delta[/tex]T

    q = M (Cs) delta T

    3. The attempt at a solution
    I tried to find the thermal temperature first by using the temperature above, but I got different temperatures that were not even close to what they should be. THe thermal temperatures should be between -10 and 20, however they are going to be closer to the 20 becuase water mass is much more than mass of ice.
    Last edited: Jun 6, 2009
  2. jcsd
  3. Jun 9, 2009 #2
    Hello there,

    You are missing a key equation:

    mc∆T = -mc∆T,

    where ∆T = Tf - Ti.

    I encourage you to learn this equation and then retry the problem. If you need any more help, please write back!
  4. Jun 9, 2009 #3


    User Avatar

    Staff: Mentor

    First - it is a very particular case.

    Second - it doesn't account for the ice melting.

    highcoughdrop: heat gained = heat lost; can you list all partial heats thet wll be lost/gained before ysstem will get to the equilibrium?
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