17. . Radioactive tracers. Radioactive isotopes are often intro-|BIO duced into the body through the bloodstream. Their spreadthrough the body can then be monitored by detecting theappearance of radiation in different organs. 131, a B emitterwith a half-life of 8.0 d, is one such tracer. Suppose a scientistintroduces a sample with an activity of 375 Bq and watches itspread to the organs. (a) Assuming that the sample all went tothe thyroid gland, what will be the decay rate in that gland 24 d(about 2 weeks) later? (b) If the decay rate in the thyroid 24 dlater is actually measured to be 17.0 Bq, what percent of thetracer went to that gland? (c) What isotope remains after the I-131 decays?

Given that:I131 is a β- emitterT1/2=8.0 dAo=375 Bq

Answered: • Radioactive tracers. Radioactive…

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