The half-life of 131I is 8.04 days. (a) Convert the half-life to seconds. s (b) Calculate the decay constant for this isotope. s−1 (c) Convert 0.650 μCi to the SI unit the becquerel. Bq (d) Find the number of 131I nuclei necessary to produce a sample with an activity of 0.650 μCi. 131I nuclei (e) Suppose the activity of a certain 131I sample is 7.10 mCi at a given time. Find the number of half-lives the sample goes through in 40.2 d and the activity at the end of that period. (Enter your answer for the number of half-lives to at least one decimal place.) half-lives mCi
The half-life of 131I is 8.04 days. (a) Convert the half-life to seconds. s (b) Calculate...
The half-life of 131I is 8.04 days. (a) Convert the half-life to seconds. (b) Calculate the decay constant for this isotope. (c) Convert 0.350 μCi to the SI unit the becquerel. (d) Find the number of 131I nuclei necessary to produce a sample with an activity of 0.350 μCi. (e) Suppose the activity of a certain 131I sample is 6.10 mCi at a given time. Find the number of half-lives the sample goes through in 40.2 d and the activity...
The half-life of 52Mn is 5.59 days. (a) Convert the half-life to units of seconds. (b) What is the decay constant (in s−1) for this isotope? (c) Suppose a sample of 52Mn has an activity of 0.510 µCi. What is this activity expressed in the SI unit of becquerels (Bq)? (d) How many 52Mn nuclei are needed in the sample in part (c) to have the activity of 0.510 µCi? E. Now suppose that a new sample of 52Mn has...
The half-life of 131I is 8.04 days. On a certain day, the activity of an iodine-131 sample is 6.36 mCi. What is its activity 37.8 days later?
1. Calculate the activity of a 200.0 g sample of natural potassium. Express your answer both in Curies (Ci) and in Becquerel (Bq). 1 Bq = 1 nuclei s−1 1 Ci = 3.700×1010 nuclei s−1 2. Technetium-99m is a metastable form of technetium-99 (isotopic mass = 98.9062547 u) and has a half-life of 6.0058 hours. How many grams of Tc-99m are required to have an activity of 50.0 μCi? 3. Ytterbium-169 is a radioactive isotope. 10.0 μg of pure Yb-169...
1. The half-life of an isotope of phosphorus is 14.2 days. If a sample contains 3.96e16 such nuclei, determine its activity.? 2. A 234-mCi sample of a radioactive isotope is purchased by a medical supply house. If the sample has a half-life of 17.4 days, how long will it keep before its activity is reduced to 28.9 mCi?
If I have a sample of I(131) with a half life of 8.04 days and an initial activity of 0.5 micro-curies. How many nuclei of I(131) are contained in this sample?
Radioactive Decay - Half-life and Activity 1 Radioactive decay - Half-life Time 0 1000 21 31 750 N 1.000.000 500,000 250,000 125,000 62,500 31.250 15.625 7813 3.506 1.953 977 51 6 500 7 BI . 101 250 125 0 tie 21.234.41516171819, 1012 Time in multiples of A radioactive sample's half-life is 30.2 years. 1 year = 365 days, 1 day = 24 hours, 1 hour - 60 minutes, 1 minute = 60 seconds (a) Find its decay constant in year...
3. Iodine-131, which is used to treat thyroid cancer, has a half-life of 8.04 days. How much time is required for 68% of the isotope to decay? a. 13 days b. 7 days c. 43 days d. 53 days e. 4 days
8. Fermium-253 has a half-life of 0.334 seconds. A radioactive sample is considered to be completely decayed after 10 half-lives. How much time will elapse for this sample to be considered gone? 9. 100.0 grams of an isotope with a half-life of 36.0 hours is present initially. How ma time will have elapsed when 5.00 grams remains? 131 (half-life = 8.040 days) to decay to 10. How long will it take for a 40.0 gram sample of 1-131 (half-life =...
V Question 5 3.03 pts Suppose a radioactive isotope has a half-life t% = 99.1 hr. How long will it take for a sample of the isotope to decay to 3.0% of its original activity? a. 218 hr b. 0.0354hr c. 348 yr d. 297 hr e. 501 hr O a Ob Ос Question 6 3.03 pts A radioactive isotope has a half-life, t% = 27.3 yr How long will it take for a 3.27 mCi sample of this isotope...