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  • May 6, 2006, 08:53 PM
    dmoney318
    Heat
    Physical Science student Estella uses an electric tea kettle to disinfect her apartment freezer with steam made from frost ice. She stuffs 2.0kg of frost ice into her kettle. The ice has an initial temperature of -20 degrees celsius. The specific heat of ice is=2100J/kg degrees celsius. The specific heat of water is=4200 J/kg degrees celsius. The specific heat of steam is =2100J/kg degrees celsius.
    The heat fusion of water is 335,000 J/kg degrees celsius. The heat of vaporization of water is= 2,260,000 J/kg degrees celsius. Please show work on all problems.

    How much heat in joules is required to warm the ice to its melting temperature, zero degrees celsius?

    How much additional heat in joules is required to boil all of the water in the tea kettle?
  • May 6, 2006, 11:51 PM
    kp2171
    First of all, as the system sticky note mentions, we dont do your homework for you.

    Pull out a formula and try it a little... talk about where you are getting stuck. But do not expect us to do you work.

    All the info you need is there.

    When you are warming a substance and going through a phase change, you are concerned about two processes... first heating to the phase change temp. but simply heating to the temp isn't enough. That temp is where the two phases are in equilibria... so its not like all the ice is becoming water. You need to add "extra" energy to get the ice to transition to water.

    You know the initial temp of the ice and the melting point. You know the change in temp and the mass. You know the specific heat of ice. Are you saying you don't understand what mathematical operations are required to get the proper units to cancel? You book will have problems just like this in it. Figure out the engery required to raise the temp. add the energy required to pass through the phase change. Ta-da.

    Then do the same process for the transition of water to gas.

    Do a little honest work and well try to help you.
  • May 6, 2006, 11:54 PM
    kp2171
    Here:

    Standard enthalpy change of fusion - Wikipedia, the free encyclopedia

    Look at the application part of this link... it's the same kind of thing that your book should have... but here's another ex.
  • May 11, 2006, 04:56 PM
    caibuadday
    Quote:

    Originally Posted by dmoney318
    Physical Science student Estella uses an electric tea kettle to disinfect her apartment freezer with steam made from frost ice. She stuffs 2.0kg of frost ice into her kettle. The ice has an initial temperature of -20 degrees celsius. The specific heat of ice is=2100J/kg degrees celsius. The specific heat of water is=4200 J/kg degrees celsius. The specific heat of steam is =2100J/kg degrees celsius.
    The heat fusion of water is 335,000 J/kg degrees celsius. The heat of vaporization of water is= 2,260,000 J/kg degrees celsius. Please show work on all problems.

    How much heat in joules is required to warm the ice to its melting temperature, zero degrees celsius?

    How much additional heat in joules is required to boil all of the water in the tea kettle?

    Q= MC(delta) T... Q= heat.. M= mass.. T= temp diff... ice frezz at 0 c evaporate (steam) at 100c... *** bring the ice to 0 c... melt the ice... boil the water... turn it into steam
  • Dec 17, 2007, 12:53 PM
    m_s
    What about heat detection?
  • Dec 17, 2007, 01:40 PM
    m_s_e_a_2020
    What about heat detection:confused:

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