How many of bismuth-214 must be prepared if the shipping time is 2 a. How much c
ID: 530819 • Letter: H
Question
How many of bismuth-214 must be prepared if the shipping time is 2 a. How much chromium would remain after 56 days? (27.5) hr? (64) b. How much would remain after 1 year? 18. The half life of radium 226 is 1602 years. If you have 500 grams of radium today how c. How much was present 168 days ago? many grams would have been present 13. If 200 g of a radioactive isotope are present at 1200 PM and 50 g remain at 200 600 PM, what is the halflife of the isotope? 19. A certain isotope has a half-life of be 60) hours. How much ofa 5.00 g sample will left after 24 hours? (0.3125) 14. Chromium-18 decays. After 6 halflives. what fraction of the original nuclei would 20. A certain isotope has a half-life of 3.25 remain? (1/64) hours. How much of a 10.0 kg sample will be left after 3 days? 2.2E-6) 15. The half-life of iodine 125 is 60 days. What fraction of iodine-125 nuclides would be 21. A certain isotope of Uranium has a half-life of 4.3 billion years. How long will it take for a 2.7 g sample to be reduced to 0.0844 g? (21.5) 16, Titanium-51 decays with a half life of 6 minutes. What fraction of titanium would remain after one hour? (1VI024) 22. A patient is administered 20 mg of iodine- 17. A medical institution requests 1 g of 131. How much of the isotope will remain in bismuth-214, which has a half life of 20Explanation / Answer
Ans 13.
The half life of the sample can be calculated by using the formula
Nt = No (1/2)t /t 0.5
Where Nt is the amount of sample left after time t
No is the initial amount of sample taken
t is the amount of time lapsed 2pm - 1pm = 1 hour here
t 0.5 is the half life period of the sample.
putting all the terms in the above given formula
5= 20 (1/2)1/ t 0.5
t 0.5 = 0.5 hour or 30 minutes
So the half life period of the sample is 1/2 hour or 30 minutes