Posted: Sun Mar 11, 2018 12:15 pm
Does anyone know how to solve exercise 15.105?
Posted: Sun Mar 11, 2018 10:22 pm
To solve 15.105, we are given:
initial mass of drug = 150 mg
half life = 4.5 hrs
1st order reaction
and t= 2 hrs
First, use the half life equation for a first order reaction to solve for the rate constant. Then, we can use the integrated rate law either a) solve for a ratio between the initial and final concentrations or b) pretend 150 mg is the initial concentration and find [A] (you'll get the same answer either way, and I think this method is easier). Since [A] is the amount that remains after two hours, 150 - [A] should give you the amount you need to re-inject the dog with.
Hope this helps!