posted by .

Nuclear medicine technologists use the Iodine isotope I-131, with a half-life of 8 days,to check thyroid function of patients. After ingesting a tablet containing the iodine, the isotopes collect in a patient's thyroid, and a special camera is used to view its function. Suppose a person ingests a tablet contaiing 9 microcuries of I-131. To the nearest hour, how long will it be until there are only 2.8 microcuries in the person's thyroid?

2.8=9*e^(-6.93 t/(8*24))

ln (2.8/9)=-6.93 t/182

solve for t in hours. I get about 31 hours

the answers are given, it is 324 hours. im just not sure how to get that.

where did you get -6.93 and 24 from?

m(t)=9x2^(-t/192) 192=24x8

2.8=9x2^(-t/192)
t=192xln(9/2.8)/ln2
t=323.4236495

## Similar Questions

1. ### CALC -- integrals!

Iodine-131 is used to treat hypo-thyroidism since it is preferentially absorbed by the thyroid and typically involves a total radiation dosage of 10,000,000 millirem. Iodine-131 has a half-life of eight days. 1. Set up the appropriate …

Iodine-131 is used to treat hypo-thyroidism since it is preferentially absorbed by the thyroid and typically involves a total radiation dosage of 10,000,000 millirem. Iodine-131 has a half-life of eight days. 1. Set up the appropriate …
3. ### chem

Iodine-131 is often used in nuclear medicine to obtain images of the thyroid. If you start with 3.6 109 I-131 atoms, how many are left after approximately 1 month?
4. ### chemistry

Iodine-131 is used to destroy thyroid tissue in the treatment of an overactive thyroid. the half-life of iodine-131 is 8.02 days. if a hospital receives a shipment of 200.0g of iodine-131, how much iodine-131 would remain after 32 …
5. ### math-natural log

Nuclear medicine technologists use the Iodine isotope I-131, with a half-life of 8 days,to check thyroid function of patients. After ingesting a tablet containing the iodine, the isotopes collect in a patient's thyroid, and a special …
6. ### Math

Please show me how to solve: Doctors can use radioactive iodine to treat some forms of cancer. The half-life of iodine - 131 is 8 days. A patient receives a treatment of 12 millicuries of iodine - 131. (A mullicurie is a unit of radioactivity.) …
7. ### Exponential Growth and Decay

Doctors use iodine-131 to treat some forms of cancer. The half-life of iodine-131 is 8 days. A patient receives a treatment of 12 millicuries. A millicurie is a unit of radioactivity. How much iodine-131 remains in the patient 16 days …
8. ### Chemistry

2. The half-life of a radioactive element is important when considering its application in medicine. For example, iodine-131 is often used in the imaging of the thyroid. The reason is that iodine is readily absorbed by the thyroid …
9. ### math

to determine whether a person has as thyroid deficiency, a radioactive iodine with a half-life of 8.2 days is injected into the bloodstream. a healthy thyroid is able to absorb all of the radioactivity. the amount, R, of radioactivity …
10. ### Science

Iodine-131 is used I'd diagnosing certain medical problems because of the short half-life, which is 8.02 days. Assume the hospital lab uses for 4.52g of iodine-131 in a month. What mass of this radioisotope remains in patients after …

More Similar Questions