Radioactive calcium-47 decays with a half-life of 4.5 days. A chemist obtains a fresh sample of calcium-47 and measures its radioactivity. She then determines that to do an experiment, the radioactivity cannot fall below 25% of the initial measured value. How long does she have to perform the experiment?

Q: Uranium-238, 238U, has a half-life of 4.51 x 109 years. How long will it take for 1.0 g of 238U to…

A:

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

A: Given Half life (t1/2) = 78.2 hours Initial amount (N0) = 45.7mg  Time (t) = 193 hours Radioactive…

Q: The half-life of radium-226 is 1.60X10³ yr. How manyhours will it take for a 2.50-g sample to decay…

A: Given :  t1/2 = 1.60 x 103 yr , [A0] = 2.50 g , [At] = 0.185 g Half-life : The time taken by any…

Q: The half-life of the radioactive isotope astatine-218 is 2.00 seconds. How long will it take for the…

A: all radioactive reactions are first order.  Here first calculate the rate constant with the help of…

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

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Q: Tritium (3H) is used in glowing "EXIT" signs located where there is no electricity for lightbulbs.…

A: Provided half life of 3H =12.26 year Provided time(t)=65.2 years The rate constant when  half life…

Q: The half-life of Uranium-238 is approximately 4.5(10°) years. How much of a 10 kilogram block of U-…

A: Given data :- Half life = 4.5 x 109 years mass of uranium = 10 kg

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: An unknown radioisotope exhibits 8540 decays per second.After 350.0 min, the number of decays…

A: Nuclear reactions are a type of chemical process which lead to the formation of some new nuclei with…

Q: The half-life of the radioactive isotope radon-222 is 3.82 days. How long will it take for the mass…

A: Recall the following expression to calculate required time of radon-222 to decay from 93.2…

Q: Americium-241 is widely used in smoke detectors. The radiation released by this element ionizes…

A: The activity for the sample can be described as the amount of the radioactive particles are…

Q: The half-life of the radioactive isotope phosphorus-32 is 14.3 days. How many days does it take for…

A: The equation for 1st order decay is:

Q: Mass spectrometric analysis of potassium and argon atoms in a Moon rock sample shows that the ratio…

A: The ratio of number of argon atoms and number of potassium = 10.3 : 1 Half life of potassium = 1.25…

Q: If a quantity decreases by a factor of 8 every 30 years, what is its half-life?

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Q: The radioactive isotope, used in the diagnosis of tumors, has a biological half-life of 47 hours. If…

A: Given  Half life ( t1/2 )         = 47 hour  Time ( t )                  = 26 hour  initial quantity…

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

A: The half-life of any radioactive element is the time in which it has been consumed half of its…

Q: 15) A sample of radioactive material contains 1030 atoms. If the half-life is 6hours, then, the…

A: Radioactive decay is the decay in which an unstable nucleus is broken into a number of smaller…

Q: The half-life of the radioactive isotope polonium-214 is 1.64x104 seconds. How long will it take for…

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Q: The isotope strontium-90 is produced during testing of nuclear weapons.  If 100.0 mg of strontium-90…

A: Given  Initial Amount of Sr - 90  (A)o = 100 mg  Half life time ( t1/2 )  =  29 years  Time ( t ) =…

Q: A sample of a newly discovered element, West Virginium, has a half-life of 288 years.  How long…

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Q: Chromium-51 is a radioisotope that is used to assess the lifetime of red blood cells The half-life…

A: Given: The half life, (t1/2)=27.7 days. The initial concentration of Cr-51=28.7 mg 981

Q: If the first-order half-life of tritium (³H) is 12.26 years, what amount of time is necessary for it…

A: Given data : half-life of tritium (³H) is 12.26 years Let the initial amount be x. Also given that,…

Q: Strontium-90 is a nuclide that is found in radioactive fallout from nuclear weapon explosions. Its…

A: Given :  Half life = 28 years

Q: Uranium-238 forms thorium-234 after radioactive decay and has a half-life of 4.5 x 10^9 years. How…

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Q: In medical application prior to having an MRI, a patient will be administered a dye containing a…

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Q: The half-life of the radioactive isotope magnesium-20 is 0.600 seconds. How long will it take for…

A: Half-life is the time required for a quantity to be reduced to half of its original value. The…

Q: Cesium-137 is part of the nuclear waste produced by uranium-235 fission. The half-life of…

A: Half-life of Cs-137 and initial mass, from which amount of Cs-137 left after 90.6 years.

Q: (Q114) A meteorite recovered from a meteor landing site in the Australian outback contains 0.438 g…

A: we have to calculate the age of meteorite

Q: The half-life of radioactive chromium-51 is 28 days. If a sample of chromium-51 has a mass of 12.0…

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Q: Tritium, 3H, is a radioactive isotope of hydrogen produced by cosmic rays in the atmosphere, where…

A: Half life means when half of the reactant has been consumed or decayed.

Q: 9. Strontium-90 is one of the products of the fission of uranium-235. This strontium isotope is…

A: The rate constant is calculated as follows,

Q: Phosphorus-32 is a radioisotope used to detect certain types of tumors. P-32 has an effective…

A: Phosphorus-32 is a radioisotope used to detect certain types of tumours. P-32 has an effective…

Q: A nuclear power plant emits into the atmosphere a very small amount of krypton-85, a radioactive…

A: Given: Half life (t1/2) = 10.76 years  Total time (T) = 25 years

Q: Radioactive iodine-131 decays with a half-life of 8.0 days. A chemist obtains a fresh sample of…

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Q: plutonium 239 produced in breeder reactors has a half-life of 24100 years how long will it take for…

A: Answer: Time for 10% decay of Pu-239 is 3665.175 years

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

A: Radioactive decay is always a first order reaction. According to the first order radioactive decay…

Q: Cobalt-60, used in cancer therapy, decays by beta and gamma emission. The decay constant is 4.18 x…

A: Expression for half-life period of radioactive element is given as, t1/2=ln2λλ-Radio active decay…

Q: 9) U-235, one of the nuclides in spent nuclear reactor fuel, has a half-life of 703 million years.…

A: Recall the following expression to calculate required time for U-235 to be reduced to 3% of this…

Q: The half-life of radioactive cobalt is 5.27 years. Suppose that a nuclear accident has left the…

A: Given the half-life of cobalt=5.27 years.

Q: Strontium-90 (90Sr) is a radioactive isotope with a half-life of 28.8 years. What percentage of this…

A: The radioactive disintegration falls in the type of first-order kinetics where reaction rate…

Q: Strontium-90 is one of the products of the fission of uranium-235. This strontium isotope is…

A:

Q: If the first-order half-life of tritium (°H) is 12.26 years, what amount of time is necessary for it…

A: The half-life is the time taken for the reaction to complete half of its original concentration

Q: Radioactive phosphorus-32 decays with a half-life of 14.0 days. A chemist obtains a fresh sample of…

A: We have to calculate the number of days chemist have to do the experiment.

Q: The radioactive decay of thallium−206 to lead−206 has a half-life of 4.20 min. Starting with 5.60…

A: All radioactive decay follows first order kinetics. So we can use the equation of first order…

Q: An unknown sample contains radioactive element U-235, If the original amount present is 3500 atoms,…

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Q: Americium-241 is widely used in smoke detectors. The radiation released by this element ionizes…

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.