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Homework Help: Gases coursework question

  1. Jan 23, 2009 #1
    A child's helium-filled balloon escapes at sea level and 20.0°C. It reaches an altitude of 3330 m, where the temperature is 5.0°C and the pressure only 0.65 atm. What is the ratio of its volume at this altitude to its volume at sea level?


    i got .94
  2. jcsd
  3. Jan 23, 2009 #2


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    Re: gases

    Did you take into account the drop in air pressure?
    What will this do to the volume of the balloon
  4. Jan 24, 2009 #3


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    Re: gases

    Also, don't forget that the pressure inside the balloon gets a contribution from the tension in the rubber.