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    Can someone explain what the components of the equation (C = C0e-kt) are please? I've searched google but I can't find anything.


    Q) After a one year storage period, an aqueous drug solution with an initial concentration of 5% (w/v) was shown by analysis to have a concentration of 45 g L-1. The drug solution is known to be ineffective if it decomposes to 70% of the initial concentration.

    Assuming first order kinetics of decomposition (C = C0e-kt), calculate the shelf life (in months) of the drug solution.

    Thank you
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    C is the concentration of the species, C0 is the initial concentration, k is the rate constant, and t is the time.

    Hope that helps!
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    I don't really get how to work it out?
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    (Original post by Princess Kawaii)
    I don't really get how to work it out?
    Same format as the beer lambert law but length is replaced with time and intensity is replaced by concentration.
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    (Original post by Princess Kawaii)
    I don't really get how to work it out?
    Hmmm I'm not sure either, seems you are missing what the rate of decomposition is?
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    (Original post by Bradshaw)
    Hmmm I'm not sure either, seems you are missing what the rate of decomposition is?
    No, we have initial concentration and the concentration after 1 year
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    (Original post by JMaydom)
    No, we have initial concentration and the concentration after 1 year
    Ah yeah, serves to read the question properly!
 
 
 
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