Radium decomposes approximately at a rate proportional to the amount present. If it is 100 grams now, and it will be 96 grams a hundred years later, find a) the half-life of the radium b) the time it takes for 2/3 of its amount to be decomposed.

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: Substance D initially weights 56 grams. After 6 minutes, it was observed that its mass decreased by…

A:

Q: The half-life of strontium-90 is 28 years. H

A: Given t1/2 of a reaction is 28 years  decay constant  (λ) λ = 0.693t1/2     = 0.69328 y     =…

Q: Iron-59 is commonly used as a source of B particles. How long does it take for 87.5% of a sample of…

A: Radio active decay is an example of 1st order reaction. and for 1st order reaction the rate law is…

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: Calculate the mass of sodium-24 that will remain in a 20.0 g sample after 75 hours. Sodium has a…

A: Chemical kinetics is branch of chemistry in which we deal with the speed at which rate of reaction…

Q: Use the radioactive decay curve of iridium-192 to answer the three questions A. If the initial…

A: Radioactive decay is the procedure in which the energy of an unstable atomic nucleus falls by…

Q: If 29.5% of the original amount of 14C is present in a wooden tool at the time of analysis, what is…

A: Since the carbon decay is a first order kinetics reaction Hence for the first order reaction we can…

Q: The half-life of cesium-137 is 30 years. Suppose we have a100-mg sample.(a) Find the mass that…

A: (a) Given half life of cesium- 137 = 30 years. For calculating mass after t years, Formula for…

Q: If 7.0 grams of a sample decays to 0.44 grams in 2.0 hours, what is the half-life time of the…

A: For calculation of half life first of all we need rate constant of the reaction, which can be…

Q: Tritium, which is , has a half-life of 12.3 years. Calculate the amount of time it would take for…

A:

Q: Iodine-131 has a half-life of 8.0 days. How long will it take 10 μg of 131I to decrease to 1/100 of…

A: We have given the half life of 131I that is t1/2 = 8 days from this we can find the out the decay…

Q: A to 240mg sample of technetium 99M is used for a diagnostic test. if Technetium -99m has a…

A:

Q: The half-life of 123I is 13 hr.  How much of a  64 mg sample of 123I is left after 26 hours?

A: The isotope of iodine, 123I, undergoes decay in accordance with first order kinetics. The half-life…

Q: The half life of radium -226 is 1590yrs . If a sample contains 400mg, how many mg will remain after…

A: Given;

Q: The half life of 21 At is 7.214 hours. What fraction of a sample of21At will remain after 3.141…

A:

Q: Carbon-14 has a half-life of 5,730 years. If a sample contained 70 mg originally, how much is left…

A: Carbon-14 has a half-life of 5,730 years. If a sample contained 70 mg originally, how much is left…

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

A: Given, Half Life , t1/2 = 28 days First, calculate rate constant ,K to calculate time (t)

Q: If we start with 1.000 g of strontium-90, 0.953 g will remain after 2.00 yr. (a) What is the…

A: As we know, that Radio active decay follows first order kinetics. Rate constant for first order…

Q: If a tree dies and the trunk remains undisturbed for 1.895 × 10ª years, what percentage of the…

A: Mass% is equal to the ratio of the mass of the given substance to the total mass of the substance.…

Q: The half-life of iron-59 is 44.5 days. How much of a 3.00-mg sample will remain after 222.5 days?

A:

Q: The time it takes for half of a radioisotope's atoms to decay (like Carbon-14) ___.   is used to…

A: Half life is the time required by a quantity or a substance to reduce to half of its initial value.…

Q: The half-life of C-14 is 5730 years. How many grams of carbon-14 will remain after 17190 years, if…

A:

Q: The half-life of phosphorus-33 is 25 days. How much of a 128-g sample will remain after 150 days?

A: Let initial amount of P-33 present initially long year back = Ao = 128 g Final mount of P-33 present…

Q: The half-life of cobalt-60 is 5.27 yr. How much of a 1.000-mg sample of cobalt-60 is left after…

A:

Q: What is the half-life of iron-55 if 5.93 years are required for the activity of a sample of iron-55…

A:

Q: The half-life of radiogold is approximately 3 days. If 1.5 g of this has been administered to a…

A:

Q: How long long does it take for 78 % of sample of cobalt-60 to decay (the half life is 5,26 years)?

A: The rate of a reaction is expressed as: Rate = k[A]n where k is the rate constant, [A] is the…

Q: The half-life of Palladium-100 is 4 days. After 12 days a sample of Palladium-100 has been reduced…

A: The initial mass of the sample of palladium-100, No, in mg is calculated as shown below where t1/2…

Q: A sample of 113m In has a half life of 100 minutes. What amount of 113m In remains (in CPM) if a…

A: An exponential decay can be described by the formula:

Q: The half-life of cobalt-60 is 5.3 years. How long will it take for a 1.000-mg sample of cobalt-60 to…

A: Given: The half-life of Co-60 is 5.3 years. The initial amount of Co-60 is 1.000 mg. The amount of…

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

A:

Q: The half-life of tritium is 12.4 years. How long will it take for 15% of a sample of tritium to…

A: The radioactive decays are first order reaction.

Q: 3. If the half-life if Iridium-182 is 15 minutes, how much of a 1 gram sample is left after 45…

A: Radioactive isotopes always undergo first order reaction. And the rate of reaction for first order…

Q: The half-life of Palladium-100 is 4 days. After 20 days a sample of Palladium-100 has been reduced…

A:

Q: 21. Half-Life The half-life of radium-226 is approximately 1620 years. a. How much of a sample…

A: Introduction: We know that this decay of radioactive elements is a type of first-order reaction. The…

Q: he​ half-life of the radioactive element unobtanium-37 is 5 seconds. If 32 grams of unobtanium-37…

A:

Q: The half-life of strontium -90 is 28 years. How long will it take a 40 mg sample to decay to a mass…

A: Given :-  Half life i.e. t1/2 = 28 years  Initial amount of sample = 40 mg  Final amount of sample =…

Q: he half-life of chromium-51 is 28 days. If the sample contained 510 grams, how much chromium would…

A: Given that

Q: The half-life of Palladium-100 is 4 davs. After 20 days a sample of Palladium-100 has been reduced…

A: The nuclear reactions of the radioactive elements are generally the first-order reactions. The…

Q: The half-life of bromine-74 is 25 minutes.  How much of a 40 cpm sample is still active after 75…

A: Since bromine-74 is a radioactive element  hence it will have decay reaction  And since the decay…

Q: Calcium – 47 has a half-life of 4.5 years . How long will it take a 100 mg sample to drop to 12.5…

A:

Q: The cesium-137 has a half life of 30 years after 90 years about 10g.remains. the original mass of…

A:

Q: what is it's half-life?

A:

Q: 5. Strontium-90 has a half life of 28.8 years. If you start with a 10 gram sample of Strontium-90,…

A: We have to predict the amount after 115.2 years.

Q: Sodium -25 has a half  life of 60.0 s. If 5.00 mg of sodium -25 disintegrated over a period of 3.0…

A: Atoms having same atomic number but different atomic masses are called isotope. For one there are…

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.