Iodine-123, which has a 13.3-hour half-life and a 25 mg initial concentration, will have 3.09 mg after 39.9 hours.
Using a first-order kinetics equation,
log C = logC0-Kt/2.302
An arrangement of chemical reactions where the rate of the reaction is proportional to the amount of the reactant and is dependent on the concentration of just one reactant.
The half-life of idodine- 123 is 13.3 hours.
from the formula of half-life K can be calculated.
The period of time it takes for a sample's ingredient to decrease by half in your body is known as the half-life.
T1/2 = 0.693/ K
13.3 hours= 0.693/K
K= 0.052 [tex]hour^{-}[/tex]
Substituting the value of K, C0, and t in the equation of first-order kinetics
logC= log(25) - 0.052 × 39.9/ 2.303
logC = 1.39-0.90
logC= 0.49
C= antilog (0.49)
C= 3.09 mg
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