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Homework Help: What mass of the ethanol is she freezing?

  1. Mar 8, 2010 #1
    A technician freezes some ethanol by removing 9.53x10^4 J of heat energy from it at its melting point. What mass of the ethanol is she freezing?
     
  2. jcsd
  3. Mar 8, 2010 #2

    rock.freak667

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    Re: help

    What equation do you think you need to use here? What information do you think you need to have to work out this problem?
     
  4. Mar 8, 2010 #3
    Re: help

    No idea
     
  5. Mar 8, 2010 #4

    rock.freak667

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    Wouldn't the technician have to lower the temperature to the freezing point? Do you know an equation that related heat energy to temperature?
     
  6. Mar 8, 2010 #5
    Re: help

    No ida
     
  7. Mar 8, 2010 #6

    rock.freak667

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    Do you know the equations Q=mcΔT and Q=ml ?
     
  8. Mar 8, 2010 #7
    Re: help

    Yes

    Q = Mas x (umm, 4200 for water :) ) x (Tf - To)
     
  9. Mar 8, 2010 #8

    rock.freak667

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    You will need to get the specific heat capacity of ethanol, the melting and freezing temperatures. Look those up.
     
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