One of the radioactive isotopes used in medical treatment or analysis is iodine-131. The half-life of iodine-131 is 8 days. How much time is required for the activity of a sample of iodine-131 to fall to 12.5 percent of its original value?

Q: If the amount of a radioactive element decreases from 0.36 g to 90. mg in 22 min, what is its…

A: Half-life (t1/2) is defined as the time required by a substance to reduce to half of its initial…

Q: A radioactive isotope has a half life of 98.9 minutes. How long will it take for the radiation from…

A: Given , Half life = 98.9 minutes Initial concentration = 325 pCi Time ,t = ?

Q: What is the half-life of bismuth-214 if 62.5 minutes are required for the activity of a sample of…

A:

Q: (11) Lead-211 is a radioactive isotope with a half-life of 36.1 minutes. How long will it take for…

A:

Q: The amount of radio active material present at time t is given by A=Aoekt, where Ao is the initial…

A: For a first order reaction, the rate of reaction is proportional to the first power of concentration…

Q: The half-life of cesium-129 is 32.0 hours. How much time is required for the activity of a sample of…

A: Radioactive decay follows the first-order kinetics. The decay constant (λ) and half-life of a…

Q: The half-life of element X is 500 years. If there are initially 8 g of X, how much will remain after…

A:

Q: A pure sample of tritium, 3H, was prepared and sealed in a container for a number of years. Tritium…

A:

Q: Gallium-67 is used medically in tumor-seeking agents. The half-life of gallium-67 is 78.2 hours. How…

A:

Q: A sample of Thorium-228 has a half life of 1.9116 years. what percent of thorium 228 remains after…

A: Let the initial amount be A0After the first half-life the amount remaining is

Q: (6) After three half-lives, 100% (A) (B) 50% (C) 25% (D) 12.5% % of the initial isotope of a…

A:

Q: The half-life of cesium-129 is 32.0 hours. How much time is required for the activity of a sample of…

A: Given  Half life of cesium - 129 =  32 hours  Remaining activity [ A ] = 14.5 %  Time ( t ) = ?

Q: Radioactive calcium-47 decays with a half-life of 4.5 days. A chemist obtains a fresh sample of…

A: Half life of sample T = 4.5 days Final radioactivity A' = (100-25) % of A = 75 % of A.  A is initial…

Q: Gallium-67 is used medically in tumor-seeking agents. The half-life of gallium-67 is 78.2 hours. How…

A: We have to predict the time taken.

Q: The answer should be 26.7 days

A: Half-life:The time taken for half disintegration of radioactive element from its original amount is…

Q: The isotope Bismuth-212 has a half life of 368.65 day. What mass in mg of a 2 mg sample will remain…

A: Half life of Bismuth, t1/2 = 368.65 days. Bismuth-212 is a radioactive element. Thus, it will follow…

Q: Cobalt-60 is a beta emitter with a half-life of 5.3 years. Approximately what fraction of cobalt-60…

A: The half life of cobalt-60 is = 5.3 year The fraction of cobalt-60 atoms will remain in a particular…

Q: What is the half-life of thallium-210 if 2.40 minutes are required for the activity of a sample of…

A:

Q: Cs-134 has a half-life of 2.0 years. How much of a 2.50-g sample of this isotope will remain after…

A: Given :- half life of Cs-134 = 2.0 years                Initial amount of sample = 2.50-g  To…

Q: Iodine-131 is administered orally in the form of NaI(aq) as a treatment for thyroid cancer. The…

A: Time required for the activity of a sample of iodine-131 to fall to 5.57 percent of its original…

Q: Radioactive radon-222, found in many homes, is a potential health hazard. The half-life of radon-222…

A: Radon 222 is a radioactive substance which undergoes radioactive decay Here we are required to find…

Q: After 119 days have elapsed, 1/12 of a radioisotope sample remains undecayed. What is the half-life…

A: Amount of radioisotopes remaining = 112 of the initial amount Number of days taken for the decay =…

Q: Radioactive radon-222, found in many homes, is a potential health hazard. The half-life of radon-222…

A: Given -> Half life = 3.82 days

Q: 17. If it takes 12 half-lives for a radioactive chemical (k = 4.85 x 10-2 day¹) to decay to a level…

A: Half-life is the time taken for half of the radioactive atoms of a specific radionuclide to decay

Q: 7. If uranium-238 has a half-life of 45 billion years, how many years would it take for a 10-gram…

A: The half-life is the time required to reduce one half of the initial concentration of the substance.

Q: A 40.0 mg sample of a radioactive substance decays to 10.0 mg in 10 days. What is the half-life of…

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Q: Gallium-67 is used medically in tumor-seeking agents. The half-life of gallium- 67 is 78.2 hours.…

A: Given   The half-life is 78.2 hours. The fall in activity of gallium-67 is 29.1 percent of its…

Q: What is the half-life of radium-226 if 3.41x10 years are required for the activity of a sample of…

A:

Q: Iodine-131 is administered orally in the form of Nal(aq) as a treatment for thyroid cancer. The…

A: We know, radioactivity is an example of first-order reaction.

Q: Thallium-201 is used medically to diagnose heart problems. The half-life of thallium-201 is 72.9…

A:

Q: If the amount of radioactive element decreases from 2.4 g to 0.30 g in 36 days, what is its…

A: Half life is defined as the time taken by the radioactive sample to decay to half its original…

Q: The half life for the decay of carbon-14 is 5.73 x 10³ years. Suppose the activity due to the…

A: We need to calculate age of the wood sample

Q: A sample of F-18 has an initial decay rate of 1.5 x 10° dis/s. How long will it take for the decay…

A: When an atomic nucleus breaks down by itself that results in the release of energy and matter, such…

Q: The half life for the decay of carbon-14 is 5.73 x 10³ years. Suppose the activity due to the…

A: Given: The half-life of carbon-14 = 5.73 × 103 years The activity of the sample = 81 Bq The activity…

Q: What is the half-life of gallium-74 if 32.1 minutes are required for the activity of a sample of…

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Q: A radioactive isotope has a half life of 60.2 minutes.How long will it take for radiation from a 325…

A: The radioactive decay of an isotope follows a first-order reaction, The integrated rate law for a…

Q: (c) Given that radioactive cobalt-60 has a radioactive constant equal to 7.6 x 10 s', determine its…

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Q: Radium-223 decays with a half-life of 11.4 days. How long will it take for a 0.240 mol sample of…

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Q: One of the nuclides in spent nuclear fuel is U-235, an alpha emitter with a half-life of 703 million…

A: Using the given half-life period, rate constant, k can be determined.

Q: What is the half-life of chromium-56 if 12.8 minutes are required for the activity of a sample of…

A: Radioactive decay follow first order kinectics . Half life for first order reaction  = 0.693/k  k is…

Q: Thallium-201 is used medically to diagnose heart problems. The half-life of thallium-201 is 72.9…

A: Radioactive decay follows the first-order kinetics. The decay constant (λ) and half-life of a…

Q: Carbon-14 is used in radiocarbon dating. The half-life of carbon-14 is 5.73*10^3 years. How many…

A:

Q: What is the half-life of thallium-209 if 4.20 minutes are required for the activity of a sample of…

A: The radioactive disintegration is a type of first order kinetics which has its half-life given as -…

Q: The currently accepted value for the half-life of radiocarbon is 5,730 years. Based on that…

A: Given: The half-life of radiocarbon = 5,730 years. We have to find which one of the given…

Q: After 119 days have elapsed, 1/21 of a radioisotope sample remains undecayed. What is the half-life…

A: Suppose the initial amount of sample be Ao After 119 days, amount remaining, A = (1/21) Ao The…

Q: Gallium-67 is used medically in tumor-seeking agents. The half-life of gallium-67 is 78.2 hours. How…

A: The decay reactions are first order reactions. Since we know that the relationship between the…

Q: What is the half-life of magnesium-20 if 1.24 seconds are required for the activity of a sample of…

A:

Q: Cobalt-60 is used extensively in medicine as a source of g-rays. Its half-life is 5.27 years. What…

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Q: A sample of Thorium-228 has a half-life of 1.9116 years. What percent of Thorium-228 remains after…

A: Applying basic concept of radioactivity.

Writing and Balancing Nuclear Equations

A nuclear equation is a symbolic representation of a nuclear reaction using certain symbols. It is studied in nuclear chemistry and nuclear physics.