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Homework Help: Integrating the first order rate law

  1. May 29, 2008 #1
    -d[A]/dt = k[A]

    - Int( d[A]/[A]) = Int (k dt)

    - ( ln[A] + ln[A0] ) = kt

    ln[A] = -kt - ln[A0]


    Where am I wrong?
     
  2. jcsd
  3. May 29, 2008 #2

    epenguin

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    - ( ln[A] - ln[A0] ) = kt
     
  4. May 29, 2008 #3
    Why "-"?
     
  5. May 29, 2008 #4
    It's always final - initial when doing integrals i.e.

    [tex]F(b) - F(a) = \int_{a}^{b} f(x) dx[/tex]

    and not +.
     
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