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Homework Help: A Leak in a Bicycle Tire Problem

  1. Dec 23, 2016 #1
    1. The problem statement, all variables and given/known data

    2. Relevant equations
    pV = nRT

    3. The attempt at a solution

    I assumed that volume and temperature would stay constant. I assumed the volume wouldn't change because the volume of the tire doesn't change. This implies that

    n1/p1 = n2/p2

    n1p2 / p1 = n2

    I found n1 by using the ideal gas law

    pV/RT = n1 = 0.0592 moles of gas

    Then I used the first equation to find n2 = 0.0431 moles.

    Subtracting n1 - n2 I found that 0.0161 moles of gas escaped from the tire.

    Converting the amount of moles lost to grams I get

    0.0161 x 28 g N2/ 1 mol N2 = 0.451 g of N2 gas

    The correct answer should be 1.8 g

    Attached Files:

  2. jcsd
  3. Dec 23, 2016 #2
    Show us how you got the initial mass of nitrogen.
  4. Dec 23, 2016 #3
    OK I see. I made an error in calculating the volume of the tire.
  5. Dec 23, 2016 #4
    The ideal gas law uses absolute pressures, not gauge pressures.
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