The half-life of 129I is 1.72 x 107 years. Consider a sample that contains 2.39 x 106 atoms of this isotope. How many of those atoms will have disintegrated after 3.44 x 107 years?

Q: The half-life of Lithium-8 (Li-8) is 0.84 seconds. If 400 grams of Li-8 were released to the…

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

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Q: If you have 1 gm of pure potassium 40 (40K) that is experimentally determined to emit about 105 beta…

A: Activity of 40 K = 105 beta rays. The decay constant λ can be calculated as follows:

Q: 21. Barium – 122 has a half-life of 2 minutes. Suppose you obtain a sample weighing 10.0 g and it…

A: 21. Given that: Half life of Barium-122 = 2 mins. Time taken for the set up = 10 mins

Q: A particular isòtope of an element has a half-life of 75.0 hours. What percentage of the sample will…

A: All isotopic decomposition follows the first order reaction kinetics. So using integrated rate…

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

A: ★ Answer : 13.712 mg of Gallium-67 remains after 112 hours. ★ Solution :

Q: The isotope nickel-63 has a half-life of 100 years. If a tested sample has five grams of nickel-63…

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Q: The half-life of a radioactive element is 1,250 years.What percent of the atoms remain after 5,000…

A: Number of half lives = 50001250 = 4 100%  →1250 years 50%  →1250 years 25% →1250 years 12.5 % →1250…

Q: Given that radioactive cobalt-60 has a radioactive constant equal to 3.8 x 10 determine its…

A: Now in order to calculate the half life we first write down the given data: Radioactive…

Q: Tellurium-123 is a radioactive isotope occurring in natural tellurium. The decay constant is 1.7 x…

A: Radioactivity is a special property of some elements or substances by which they continuously…

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

A:

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: In a moon rock sample, the ratio of the number of stable 4°Ar atoms present to the number of…

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Q: The half life of Carbon-14 is 5730 years. Calculate what percentage of C-14 will remain after 17,190…

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Q: The radioisotope radon-222 has a Half-Life of 3.8 days. How much of a 73.9-g sample of radon-222…

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Q: 2Bi is a radioactive isotope of the element bismuth with a half-life of 19.7 minutes. What…

A: Given: half-life of isotope of bismuth is 19.7 minutes.

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: The half-life of mercury-203 is 46.6 days. What percentage of mercury-203 remains in a sample after…

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Q: The isotope ²¹²₈₃Bi has a half-life of 1.01 yr. What mass (inmg) of a 2.00-mg sample will remain…

A: Given, half life of  ²¹²₈₃Bi ,  t1/2 = 1.01 yr = 365 x 24 x 1.01 h = 8847.6 h            initial…

Q: " Ca is used in the study of bone formation. The half-life of Ca is 4.54 days. If you begin with…

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Q: The decay constant for the element X is 6.931 yr⁻¹. What is the half-life?

A: Relation between decay constant (K) and half life (t12) of an element:-t12 =0.693K

Q: Americium-241 is a radioactive isotope that is used in smoke detectors. It has a half-life of 432.2…

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Q: The half-life of a certain radioactive element is 800 years. How old is an object if only 12.5% of…

A: Given, Half Life t1/2 = 800 years. A = 12.5%  Ao = 100 %  Time , t = ?

Q: The half-life time of a radioactive element is 6.0 days. A sample of 50.0 g of this element is…

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

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Q: The half-life of Radium-226 is 8 years. How much of an initial 171 g sample will remain after 43…

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Q: Q1: If you know that the half-life of a radioactive element is equal to 20 days, find the following:…

A: Radioactive active decay generally follows a first order reaction and therefore, the rate of…

Q: 214Bi is a radioactive isotope of the element bismuth with a half-life of 19.7 minutes. What…

A: Welcome to bartleby !  Introduction :  We have to calculate percentage of bismuth lost . Given :…

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

A: Given Half life of Radon -222 ( t1/2 )  = 3.82 days  Initial amount of isotope ( A0 )= 33.5 mg  Time…

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

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Q: Chemistry An unknown radioactive substance has a half-life of 3.20 hourshours . If 34.7 gg of the…

A: All natural and artificial radioactive decays follows first order kinetics The integrated rate…

Q: A radioactive sample initially contains 2.40×10^−2 mol of a radioactive material whose half-life is…

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Q: Naturally occurring uranium is composed mostly of 238U and 235U, with relative abundances of 99.28%…

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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: Carbon-14 is a radioactive element with a half-life of about 5,730 years. Carbon-14 is said to decay…

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

A: Gallium - 67 has a half-life of 78.2 hours. Initially 36.7 mg of Gallium - 67 were present.   Here,…

Q: The half-life of 90Sr is 29 years. What fraction of the atoms in a sample of 90Sr would remain 175…

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Q: Naturally occurring uranium is composed mostly of 238U and 235U, with relative abundances of 99.28%…

A: Given, relative abundance : U238=99.28 % U235=0.72% Half life : t1/2 of U238=4.5×109 yr t1/2 of…

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

A: Since you have asked multiple questions, we will solve the first question for you. If you want any…

Q: 1. Gold-198 is used in the diagnose of liver problems. The half-life of Au is 2.69 day. If you begin…

A: Given data: half life of 198Au = 2.69 day Initial concentration of  198Au is 2.8 μg Time = 10.8 day

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

A: The half life of radon = 3.82 days. Initial amount = 37.9 mg  time = 4.70 days mass remains after…

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

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

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Q: The half-life of 98AU is 2.7 days. If you begin with 5.6 mg of this gold isotope, what mass remains…

A: Half-life is the time required for the reaction to be half completed. It is denoted by t1/2 . For a…

Q: Iodine-131 is used in the diagnosis and treatment of thyroid disease and has a half-life of 8.0…

A: Formula: Since Iodine is a radioactive substance, it follows the 1st order rate law. The half-life…

Q: Naturally occurring uranium is composed mostly of 238U and 235U, with relative abundances of 99.28%…

A: Decay constant for 238U can be calculated as: λ=0.693t12=0.6934.5×109years-1 Decay constant for 235…

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

A:

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.