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In your lab you are studying the kinetics of the degradation of a pain killer in

ID: 1057292 • Letter: I

Question

In your lab you are studying the kinetics of the degradation of a pain killer in the human liver. You are monitoring the concentration of the pain killer over a period of time. The initial concentration of the pain killer in your experiment was 1.53 M. After 11.10 hours the concentration was found to be 0.7650 M. In another 22.19 hours the concentration was found to be 0.3825 M (t = 33.29 hours overall). If another experiment were set up where the initial concentration of the pain killer was 0, 307 M, how long would it take for the pain killer concentration to reach 0.0221 M?

Explanation / Answer

[A]0 = 1.53 , t1 = 0

t2 = 11.1 --> [A] = 0.7650

t3 = (22.19 +11.1) = 33.29 --> [A]3 = 0.3825

find time required for [A]4 = 0.0221

So..

assume this is first order so:

K from graphj --> 0.0402

so

Rate = K[A]

solved

ln(A) = ln(A0) - kt

find t for

ln(0.3825) = ln(1.53) - 0.0402 * t

t = -(ln(0.3825)- ln(1.53) ) /(0.0402) = 34.484 hours (from initial time)

34.484 -33.29 = 1.194h after third point