Question

Technetium-99m, a gamma emitter, is primarily used to image the brain, skeleton and lungs to locate tumors or an infection. It decays radioactively by first order kinetics with k=0.115 hr⁻¹.

What is the half-life of Technetium-99m?
a. T_1/2 = ln(2)/k
b. T_1/2 = k/ln(2)
c. T_1/2 = 1/k
d. T_1/2 = ln(2)/2k
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Answer 1

The half-life of Technetium-99m is calculated using the formula T_1/2 = ln(2)/k, which equals approximately 6.01 hours for k = 0.115 hr⁻¹.

Step-by-step explanation:

The question asks for the half-life of Technetium-99m given its decay rate constant (k) using first order kinetics. The half-life (T_1/2) of a substance can be calculated using the formula T_1/2 = ln(2)/k. Thus, for Technetium-99m with k = 0.115 hr⁻¹, its half-life is T_1/2 = ln(2) / 0.115 hr⁻¹. Performing the calculation yields a half-life of approximately 6.01 hours, which aligns with the known half-life of Technetium-99m used in medical applications.