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Homework Help: Calculating enthalpy change

  1. Jan 25, 2007 #1
    When 90cm^3 of methane is burned, the heat produced is used to raise the temperature of 100 cm^3 of water from 20.0°C to 50.0C. Calculate the enthalpy change for the reaction.

    I'm not getting the same answer as the textbook....Please tell me whether my method is correct

    All you do here is use the formula mass x specific heat capacity x change in temp. So,
    the enthalpy change would be -(100/1000) x (4.18) x (30) = -12.54 KJ ?
     
  2. jcsd
  3. Jan 25, 2007 #2

    Gokul43201

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    1. For questions of this kind, please use the Homework & Coursework subforum.

    2. You've found the heat produced in burning 90cc of methane. How is the enthalpy of combustion defined?
     
  4. Jan 28, 2007 #3
    the change in enthalpy of the total reacting system
     
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