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Homework Help: Please help calorimetry problem

  1. Sep 1, 2010 #1
    1. The problem statement, all variables and given/known data
    What mass of ice at -10.0 degrees celsius is needed to cool a whale's water tank, holding 1.20 x 10^3 m^3 of water, from 20.0 degrees down to a more comfortable 10 degrees.

    2. Relevant equations

    Q = mc *delta T

    Q = mL

    3. The attempt at a solution

    i'm trying to fill out a table with knowns and unknowns before I actually solve the problem. This is what i got, can someone help me with the temperatures?

    ICE: mass = x
    c = 2090 J/kg C
    Ti = -10.0
    Tf = 0

    MELT: mass = x
    L = 3.33 x 10^5

    ICE - WATER: mass = x
    c = 4190
    This is where i'm stuck what's the temperature?
    Ti = ?
    Tf = ?

    WATER: mass = ??
    c= 4190
    Ti = 20.0
    Tf = 10

    Can someone let me know where i went wrong?? I still need to find the mass of water.

  2. jcsd
  3. Sep 1, 2010 #2
    Do you know the concept of density? as in mass per volume? you can use that to calculate your waters mass.

    As for the final temperature of the water you should calculate how much heat it needs to give up. Then see how much heat the ice can give up...
  4. Sep 1, 2010 #3
    Yes, i know about density. To get mass, just multiply density of water and volume given.
  5. Sep 1, 2010 #4
    then you can use that to get the heat water needs to give for the temperature drop. Then you can use algebra to solve for the change in the ices temperture/ melting.
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