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

  1. Mar 8, 2010 #1

    MacoRules94

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    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?
     
    MacoRules94, Mar 8, 2010
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  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?
     
    rock.freak667, Mar 8, 2010
  4. Mar 8, 2010 #3

    MacoRules94

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    Re: help

    No idea
     
    MacoRules94, Mar 8, 2010
  5. Mar 8, 2010 #4

    rock.freak667

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    Re: help

    Wouldn't the technician have to lower the temperature to the freezing point? Do you know an equation that related heat energy to temperature?
     
    rock.freak667, Mar 8, 2010
  6. Mar 8, 2010 #5

    MacoRules94

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    Re: help

    No ida
     
    MacoRules94, Mar 8, 2010
  7. Mar 8, 2010 #6

    rock.freak667

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    Re: help

    Do you know the equations Q=mcΔT and Q=ml ?
     
    rock.freak667, Mar 8, 2010
  8. Mar 8, 2010 #7

    MacoRules94

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    Re: help

    Yes

    Q = Mas x (umm, 4200 for water :) ) x (Tf - To)
     
    MacoRules94, Mar 8, 2010
  9. Mar 8, 2010 #8

    rock.freak667

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    Re: help

    You will need to get the specific heat capacity of ethanol, the melting and freezing temperatures. Look those up.
     
    rock.freak667, Mar 8, 2010
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