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Homework Help: Introduction to Thermodynamics - Two Basic Problems

  1. Feb 24, 2008 #1
    The problem statement, all variables and given/known data

    1. A kettle holding 1 lt. of water is boiling. Assuming water is evaporating at a constant evaporation rate of 1g/min, determine how long it will take for the kettle to dry out.

    2. Another kettle holding 1 lt. of water and 20g of salt is also boiling. Again water evaporates at a rate of 1g/min. This time you are asked to derive a mathematical relationship for how salt concentration in the kettle changes with respect to time.
  2. jcsd
  3. Feb 25, 2008 #2
    I need Help!!!!!!!!!!!!
  4. Feb 25, 2008 #3


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    Staff Emeritus
    Science Advisor
    Gold Member

    These are so easy that it's difficult to give you a hint without telling you the complete answer, but here's a try:

    1. 1 liter weighs 1 kg.

    2. The amount of water in the kettle (actually the weight in grams) after t seconds is 1000-t/60.
  5. Feb 25, 2008 #4
    WELCOME TO pf .

    Show some work before we take over ur problem.

    We just help in your homework ..we dont solve it buddy.
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