Fluorine-18 is a radioactive isotope that decays by positron emission to form oxygen-18 with a half-life of 109.7 min. (A positron is a particle with the mass of an electron and a single unit of positive charge; the equation is SIF 0+e.) Physicians use 18F to study the brain by injecting a quantity of fluoro-substituted glucose into the blood of a patient. The glucose accumulates in the regions where the brain is active and needs nourishment. (a) What is the rate constant for the decomposition of fluorine-18? (b) If a sample of glucose containing radioactive fluorine-18 is injected into the blood, what percent of the radioactivity will remain after 5.59 h? (c) How long does it take for 99.99% of the 18F to decay?

Fluorine-18 is a radioactive isotope that decays by positron emission to form oxygen-18 with a half-life of 109.7 min. (A positron is a particle with the mass of an electron and a single unit of positive charge; the equation is SIF 0+e.) Physicians use 18F to study the brain by injecting a quantity of fluoro-substituted glucose into the blood of a patient. The glucose accumulates in the regions where the brain is active and needs nourishment. (a) What is the rate constant for the decomposition of fluorine-18? (b) If a sample of glucose containing radioactive fluorine-18 is injected into the blood, what percent of the radioactivity will remain after 5.59 h? (c) How long does it take for 99.99% of the 18F to decay?

Chemistry by OpenStax (2015-05-04)

1st Edition

ISBN:9781938168390

Author:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark Blaser

Publisher:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark Blaser

Chapter12: Kinetics

Section: Chapter Questions

Problem 46E: Fluorine-18 is a radioactive isotope that decays by positron emission to form oxygen-18 with a...

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Fluorine-18 is a radioactive isotope that decays by positron emission to form oxygen-18 with a half-life of 109.7 min. (A positron is a particle with the mass of an electron and a single unit of positive charge; the equation is F918O188+e+10 Physicians use 18F to study the brain by injecting a quantity of ?uoro-substituted glucose into the blood of a patient. The glucose accumulates in the regions where the brain is active and needs nourishment. (a) What is the rate constant for [lie decomposition of ?uorine-18? (b) If a sample of glucose containing radioactive fluorine-18 is injected into the blood, what percent of the radioactivity will remain after 5.59 h? (c) How long does it take for 99.99% of the 18F to decay?
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