Strontium-90 has a half-life of 28.1 years. Starting with 3.2 mg of this isotope, how much...
The radioactive isotope Cs-137 has a half-life of 30 years. Starting with 1.0 mg of Cs, how much would remain after 90 years?
The Strontium-90 isotope has a half-life of 28.1 years. Supposed we used a .10 Curie sample of Sr-90. That is, we used enough Sr-90 to have an activity of .10 Ci (1 Ci=3.7x1010 disintegrations/second) Calculate the activity of this sample when used by students 281 years from now.
An isotope of cesium (Cesium-137) has a half-life of 30 years. If 1.0 mg of cesium-137 disintegrates over a period of 90 years, how many mg of cesium-137 would remain? 14. Thallium-208 has a half-life of 3.053 min. How long will it take for 120.0g to decay to 7.500 15. Element-106 has a half-life of 0.90 seconds. If one million atoms of it were prepared, how many atoms would remain after 4.5 seconds? 16. A 2.5 gram sample of an...
Yttrium 90, which has a half-life of 64.2 h, is produced from the fission product strontium 90 which has a half-life of 27.5 years. How much Y-90 will be present after I week from a sample of pure Sr-90 in a closed container? Ans.: 0.00027
Ch.20 #9
Enter your answer in the provided box. Strontium-90 is one of the products of the fission of uranium-235. This strontium isotope is radioactive, with a half-life of 28.1 years. Calculate how long (in years) it will take for 8.93 g of the isotope to be reduced to 0.430 g by decay. yr
One radioactive material that is produced in atomic bombs is the isotope strontium-90, which has a half-life of 28 years. If a person is exposed to strontium-90, it can collect in human bone tissue, where it can cause leukemia and other cancers. If an atomic bomb test site is contaminated by strontium-90, how long will it take for the radioactive material to decay to 30% of the original amount? (Round the growth factor to eight decimal numbers. Round your answer...
The isotope given below has a half-life of 1.01 yr. What mass (in mg) of a 2.00−mg sample will remain after 3.75 × 103 h? 212 Bi 83
(4 points) The half-life of radioactive strontium-90 is approximately 32 years. In 1964, radioactive strontium-90 was released into the atmosphere during testing of nuclear weapons, and was absorbed into people's bones. How many years does it take until only 9 percent of the original amount absorbed remains? time = 1 years
Isotope X has a half-life of 9.30 years. How long will it take for a 51.4 mg sample of X to decay to 0.415 mg? 69.1 Years 20.1 Years O 61.5 Years 0 64.7 Years O 89.0 Years
9. Strontium-90 has a half-life of 28.8 years and has the same basic chemical properties as calcium. The nuclear testing 60 years ago resulted in some small amount of radioactive strontium-90 residing in all of our bones (us old folks, at least). Assuming the contamination remained in the body all those years, calculate the fraction ( N / No ) of that initial contamination still present in our bones. *Please include a diagram