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Latent heat of vaporisation question

  1. Sep 27, 2012 #1
    1. The problem statement, all variables and given/known data
    A pupil performing an experiment finds that, when the heat supply is 16W, it takes 30 mins for the temp of the water to rise from 20°C to 100°C, and that the rate of evap is very
    slow even at the latter temp. Estimate an upper limit to the value of the heat capacity of the inner flask and its contents. Calculate the mass of water collected after 30mins of steady boiling when the power supply is 60W.

    (lv of water = 2.26 x 10^6 J/Kg)

    The attempt at a solution

    For the upper limit i did this
    total heat supplied= 16 x 30 x 60= 28,880J

    C= E/Δt= 28,800/80 = 360 J/K.

    Now for the mass of water I get confused with what to do
  2. jcsd
  3. Sep 28, 2012 #2
    Does the problem as reproduced here on this forum include all the information provided in the original problem statement?
  4. Sep 28, 2012 #3
    Nevermind I figured it out. xD
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