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Evgesh-ka [11]
3 years ago
15

If the amount of radioactive iodine-123, used to treat thyroid cancer, in a sample decreases from 3.2 to 0.4 mg in 39.6 h, what

is the half-life of iodine-123?
Chemistry
1 answer:
9966 [12]3 years ago
4 0

Answer:

Half life = 13.197 hour

Explanation:

Given:

Old amount (A₀) = 3.2

New amount (A) = 0.4

Radiation decay time (t) = 39.6 hour

Half life = T(1/2)

Find:

Half life = T(1/2) = T

Computation:

A = A₀e^{-(\frac{0.693t}{T} )}

e^{-(\frac{0.693t}{T} )} = 0.4 / 3.2

-[27.4428 / T] = In (0.125)

-[27.4428 / T] = -2.0794

[27.4428 / T] = 2.0794

T = 13.197

Half life = 13.197 hour

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