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Mixing problems

  1. May 31, 2005 #1
    Can anyone help me out with mixing solution problems, I know its not that hard I just am having trouble understanding what to do. Sometimes its X sometimes its X/volume of the tank. Can anyone explain it to me in a simple way?
  2. jcsd
  3. Jun 1, 2005 #2
    If you give us a sample problem maybe we could help break it donw for you?
  4. Jun 1, 2005 #3
    A swimming pool whose volume is 10,000 gal contains water that is .01% chlorine. Starting at t=0, city water containing .001% Cl is pumped in at 5 gal/min. The pool water flows out at the same rate. What is the % of chlorine in the pool after 1 hr? When will the pool be .002% Cl ?
  5. Jun 1, 2005 #4


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    Can you post an attempt?, it'll figure out what you are not understanding.
  6. Jun 29, 2005 #5
    it seems you dont know how to set up the prob. you need to find y(60).
    to do this you let y(t)=the amount of cl in the pool at time t. you need to find an expression for dy/dt.

    dy/dt = rate in - rate out

    rate in =5 gal / min * .001%

    rate out = y(t) / 10000 * 5 gal / min

    so dy /dt = (5 gal/min * .001%) - (y(t) / 10000 * 5 gal/ min)

    you then find the I.F. and intergrate
  7. Jun 29, 2005 #6


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