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lauren1x12
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Report Thread starter 4 years ago
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Can someone explain how to do this confused over it -.- not sure if I'm pressing the right thing on the calculator?

The concentration C of a drug in the blood decreases exponentially with time t according to the equation C = C0exp(-λt) where C0 is the initial concentration and λ is the decay constant. If λ is 0.03 min-1 and C0 is 1.5 μM, what is the value of C after 30 min?
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ghostwalker
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Report 4 years ago
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(Original post by lauren1x12)
Can someone explain how to do this confused over it -.- not sure if I'm pressing the right thing on the calculator?

The concentration C of a drug in the blood decreases exponentially with time t according to the equation C = C0exp(-λt) where C0 is the initial concentration and λ is the decay constant. If λ is 0.03 min-1 and C0 is 1.5 μM, what is the value of C after 30 min?
I get 0.610 to 3 sig.fig., or 0.60985448... on the calculator.

Start with the - lambda t, which you should have as -0.03 x 30 = -0.9

Work out e^-0.9 and then multiply by 1.5
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