If a rock contained 12.0 g of 4°K when the earth was formed 4.54 billion years ago and the half-life of 4°K is 1.25 billion years, what mass of 4°K remains, in grams, in the rock today? g

Q: How long does it take for a radioactive substance to decay from 360 cps to 11.25 cps if the…

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

Q: Thorium-234 has a half-life of 24.1 days. Suppose the initial amount of Thorium-234 is 162.9 mg,…

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

Q: Carbon-14 measurements on the linen wrappings from the Book of Isaiah on the Dead Sea Scrolls…

A: Given in the question, 79.5% of the carbon-14 is found in living tissue. Half life of C-14 = 5730…

Q: Strontium-90 Original amount: 5 g Amount left: 0.3125 g Total time: Half-life: 28.8 y Number of…

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Q: 1. A substance has a mass of 5 grams after decaying for 100 minutes. What was the mass of the…

A: Given that: Mass of substance left after decaying = 5 g Total time for decaying of substance = 100…

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

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Q: If a rock contained 12.0 g of ⁴⁰K when the earth was formed 4.54 billion years ago and the half-life…

A: Given information is as follows; Initial mass of ⁴⁰K in the rock A0 = 12.0 g Final mass of ⁴⁰K in…

Q: Technicium-104 has a half-life of 18 minutes.If the initial mass is 100.0g,how much remains after 90…

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Q: Moonrock collected by a US Apollo mission is estimated to be 4.30 billion years old by uranium/ lead…

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Q: A substance has a half-life of 2.045 minutes. If the  initial amount of the substance was 132.8…

A: Given,  Half-life, t1/2  = 2.045 minutes Initial ammount, A0 = 132.8 gram

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

A: Given  Half life of U-238 (t1/2)   = 45 billion years 1 billion years    = 109 years  45 billion…

Q: Cobalt-60 has a half-life of 5.3 years. How many half-livesoccur after 21.2 years?

A: Generally, a radioactive decay reaction takes place as a first order reaction.  In a first order…

Q: An artifact is found that has 33% of the 14C it had when it was living. How long ago was this…

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Q: Cesium-137, which has a half-life of 30.2 yr, is a componentof the radioactive waste from nuclear…

A: The required formula is:

Q: Enter your answer in the provided box. A rock sample originally contains 3.20 mg of 238U. How much…

A: Given data  Initial amount of 238U : No= 3.20 mg final amount of 238U : N = ? mg half life  : t1/2 =…

Q: A radioactive isotope has a half-life of 11 minutes.  How many grams of a 18.68 g sample remain…

A: Given Half life = 11minutes = 11*60= 660 second Sample weight = 18.68g Time = 44 minutes = 44*60=…

Q: The half-life of Radium-226 is 1600 years. If 30 grams are left after 8,030 years, how many grams…

A: Radioactive decay follows first order kinetics.  k = 0.693/t0.5  Or, k = 0.693/1600 year^-1 =…

Q: 3. An archeologist unearths a bone sample and wants to know the age of the initial amount of…

A: Given:  Present amount of bone = 49 %  Half life = 5730 years

Q: 32) The charcoal from ashes found in a cave gave 3.34 14C counts per gram per minute. Wood from the…

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Q: A small figure carved from wood, believed to predate the period of Roman occupation of the Middle…

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Q: A wooden statue found in Egypt has a carbon-14 content that is three-fifths of that found in living…

A: Given: A wooden statue found in Egypt has a carbon-14 content that is three-fifths of that found in…

Q: about how much would have been left after three half-lives? A parent isotope has a half-life of 500…

A: Note : As per guidelines we can answer only the first question   The time it takes for the…

Q: el The half-life of barium-131 is 12 days. How many grams remains after 60 days if the initial…

A: We have to predict the amount left after certain time.

Q: A sample of coral has a carbon-14 content of 12.5% the value of living coral.  If the half-life of…

A: Given  Half life of Carbon - 14 = 5730 years Remaining amount   = 12.5 %  Time ( t ) = ?

Q: The initial amount of thorium-232 in a rock is determined to be 6.78mg. it now has 5.32 mg of…

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Q: A wooden object from a prehistoric site has a carbon-14 activity of 10 counts per minute (CPM)…

A: Given: Half-life = 5730 years [A]=10 cpm [A]0 = 40 cpm

Q: A radioactive waste from a clinical laboratory contains 0.2 µCi (microcuries) of calcium-45 (45Ca)…

A: Answer -

Q: A moon rock collected by a U.S. Apollo mission is estimated to be 3.70 billion years old by…

A: Calculate the value of rate constant (k):

Q: carbon as a piece of modern charcoal. How long ago was the tree burned to make the ancient charcoal?…

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Q: 1. If the amount of the parent isotope in the original sample of a rock had been 48 grams, about how…

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Q: Calculate the age of a fossil that had 100 g of C-14 and now it has 12.5 g of C-14. The half-life of…

A: Use first order kinetic formula to get answer. Half life is given in years so we can use first order…

Q: The half-life of copper-67 is 61 hours.  If an original sample contains 24 grams how many grams are…

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Q: 10. The 14C content of an ancient piece of wood was found to be one-sixteenth of that in living…

A: The question is based on the concept of carbon dating. We have been given the fraction of carbon…

Q: percentage of his original carbon-14

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Q: 20. At the time an item was produced, 0.01 of the carbon it contained was carbon-14, a radioisotope…

A: Solution

Q: A moon rock collected by a U.S. Apollo mission is estimated to be 3.50 billion years old by…

A: Given : Time = 3.50 billion years old. Mass of uranium-238 = 1.540g Half life = 4.47 x 109 years

Q: The half-life of carbon-14 is 5730 years. The wrapping of an Egyptian mummy gave off 3.8 counts per…

A: From the given data we haveHalf life of carbon-14=5730 yearsWrapping of mummy=3.8…

Q: A rock contains a Pb-206 to U- 238 mass ratio of 0.262: 1.00. Assuming that the rock did not contain…

A: The answer to the following question is-

Q: carbon-14 activity

A: Given data, Basic equation is Ae = Ao x 0.5 (t / t1/2)   Therefore,

Q: rock containing 238U and 206Pb was examined to determine its approximate age. The molar ratio of…

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Q: A rock contains a Pb-206 to U-238 mass ratio of 0.473:1.00. Assuming the rock did not contain any…

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Q: 12. A year ago there were 4 grams of a radioactive substance. Now there are 3 grams. How much was…

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Q: After 103 days, only 2.3 g of a radioisotope remains from a sample that originally has 150 g of it.…

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Q: After 60 days, 10 grams of radioactive isotope remains from an original 38 g sample. What is the…

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Q: Polonium 209 (Po-209) has a half life of 103 years. How long would it take a 100-g sample to decay…

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Q: A wooden object from an archeological site is subjected to radiocarbon dating. The activity due to…

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

Q: Os-182 has a half-life of 21.5 hours. How many grams of a 10.0 gram sample would have decayed after…

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Q: Thorium-227 has a half-life of approximately 19 days. What percentage of an original amount of…

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