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Can someone please show me how to do this equation

  1. Feb 10, 2014 #1
    The temperature inside a closed vessel is 70 degrees F and the pressure of the contained gas is atmospheric pressure (14.7 PSIA).

    If the temperature increases to 100 degrees, what is the pressure (measured in PSIA) inside the vessel? Show the equation and your calculations below.

    Here is my answer

    14.7 14.7
    ── = ───
    70 100
     
    Last edited: Feb 10, 2014
  2. jcsd
  3. Feb 10, 2014 #2
    What equation are you using? I would suggest the ideal gas law.
     
  4. Feb 10, 2014 #3

    SteamKing

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    If you are working with any type of ideal gas law, you should know that you ALWAYS work with absolute temperatures.
     
  5. Feb 10, 2014 #4

    BvU

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    Do I read ##{14.7\over 70} = {14.7\over 100}## ?
    Your divisions are a little tough to read because in this forum multiple spaces are combined to 1 space, and there are no tabs (methinks).

    Anyway: That's a tough cookie! No way to solve...
    Quote me and correct me if I am quoting you wrongly.
     
  6. Feb 10, 2014 #5
    I need some help with this equation

    I understand how to do the first part but i need help with the second part

    The temperature inside a closed vessel is 70 degrees F and the pressure of the contained gas is atmospheric pressure (14.7 PSIA).

    1. If the temperature increases to 100 degrees, what is the pressure (measured in PSIA) inside the vessel? Show the equation and your calculations below.

    Answer 14.7 x (70 + 460) / (100 + 460) = 15.53

    2. What is the pressure measured in PSIG at 70 degrees?
     
  7. Feb 10, 2014 #6

    Simon Bridge

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    Please show your reasoning and your best attempt as the question.
    Don't forget to include units in your answers.

    Do you not know how to convert PSIA to PSIG?
    i.e. the difference between absolute and gauge pressures?
    http://en.wikipedia.org/wiki/Pounds_per_square_inch
     
  8. Feb 10, 2014 #7

    berkeman

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    (Moderator Note -- 2 threads merged)
     
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