(19] There are 40 grams of radioactive substance at one point in time. After two hours, only 30 grams of the substance are radioactive. What is the half-life of the substance? (note: This is very unstable stuff!)

Q: A normal adult jawbone contains 200mg of Carbon-14 in a living person. If scientists found a jawbone…

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

Q: A precursor of modern-day bison is Bison latifrons. A fossil found in North Dakota was dated with…

A: Given that : The half-life of 14C is 5730 years. The initial concentration of 14C is 100 %. Out of…

Q: A sample of wood from an Egyptian mummy case has a specific activity of 9.41 d/min-g. How old is the…

A: Solution: We know that --- for a sample of wood from an Egyptian mummy which is related to…

Q: (28) An archaeologist claims that a bone in her collection is from a saber-toothed tiger that is…

A: Given that, for a carbon-14 The initial decay rate is -dNdt0 = 15.3 disintegrations per minute per…

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

A:

Q: How many rads does a 69−kg human receive each year from the approximately 10−8 g of 14C naturally…

A: We have given Half Life = t1/2 = 5730 yearsas we know kt1/2 = ln 2k = 0.693t1/2k = 0.6935730 yr…

Q: Fluorine-18, which has a physical half-life of 110 min, is used in PET scans. if 1.00g of…

A: The fluorine-18 sample was shipped at 5:00 PM and arrives the laboratory at 9:30 AM in the next…

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

A:

Q: A moisture density gauge uses à radioactive source containing the isotope Cs-137, which has a…

A: Cs-137 has a half-life of 30.17 years . Activity of the radioactive source is 8.00 mCi, when…

Q: In a dusty corner of a spooky abandoned lab, you find a vial labeled “70g of iron-55”.  You weigh…

A: Welcome to bartleby !  We have to calculate time required

Q: A 3.6-kg laboratory animal receives a single dose of 8.92×10-4 Gy. (a) How many rads did the animal…

A: (a) Given data contains, Mass of laboratory animal is 3.6-kg. Dose received is 8.92x10-4 Gy.

Q: The smallest C-14 activity that can be measured is about 0.20%. If C-14 is used to date an object,…

A: Given :          C-14 activity measured is = 0.20% We have to calculate object died within how many…

Q: 40. Tc-99 is often used as a radioactive tracer in several medical diagnostic procedures. It has…

A: Radioactive decays are first order decay reactions. Since we know that, for different order of…

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: The radioactive isotope 125 I has a half-life of 60 days. A sample of this isotope is prepared for a…

A:

Q: Which of the following conditions is not necessary for a sustained chain reaction ? A) Fast moving…

A:

Q: Carbon-14 Dating A wooden artifact from an ancient tomb contains 65% of the carbon-14 that is…

A: Given information is as follows; Half life = 5730 years Fraction remaining = 65% = 0.65 The given…

Q: A sample of wooden artifact is found to undergo 9.0 6C 1? disintegrations per minute per gram of…

A: Given: The activity of wood sample = 9.0 disintegrations per min. The activity of fresh wood = 15…

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

A: Given half-life of U-238, t1/2 = 4.500*109 year  Decay constant, λ = 0.693t1/2 => λ =…

Q: A radioactive sample contains 1.55 g of an isotope with ahalf-life of 3.8 days. What mass of the…

A: Radioactive isotopes may occur naturally or be artificially produced. Radioactive isotopes possess…

Q: Some mammoth bones found in Arizona were found by carbon-14 dating to be 1.13x104 years old. What…

A: Given: Original activity = 15.3 disintegrations per minute per gram. Age of bones = 1.13 × 104…

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

A: Answer -

Q: some mammoth bones found in Arizona were found by Carbon-14 dating to be 1.113 x 1014 years old.…

A: We have The half-life of C14 is 5730 years t12=0.693k.......1 By rearranging the equation 1, we get…

Q: 4. Which component is not typically found in a nuclear reactor facility?

A: To solve this problem we will have to know about the given terms in the option .

Q: 22. A normal adult jawbone contains 200 mg of Carbon-14 in a living person. If scientists found a…

A: Given initial Concentration of C-14         = 200 mg Remaining Concentration of C-14 = 50  mg  Half…

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 4520Ca has a Half-Life t1/2 of 163 days. the value of the radioactive constant λ in day-1 is:

A: Please find the attached images for the answer

Q: A sample of wood from an Egyptian mummy case has a specific activity of 4.71 d/min g. How old is the…

A:

Q: You are working in a facility with a linear accelerator which may be used to measure the level of C…

A: Radioactive decay is a process in which unstable atomic nuclei emit energy in the form of…

Q: Radioactive isotopes used in cancer treatment have a shelf life simply because the active nuclei…

A: Answer :-  The source is barely (just) usable.…

Q: A piece of a spear handle is found in an archaeological dig in Central America. It contains 35.2% as…

A:

Q: When a radioactive isotope 86Ra228  decays in series by the emission of three α-particles and a β…

A: We know that: Decay of one alpha particle reduces the atomic number(Z) by 2 units and mass number…

Q: ty due to the radioactive decay of the carbon-14 in a tiny sample of an artifact made of wood from…

A: Answer: the half life carbon -14 is = 5.73 × 103 years.  Activity of the sample in initial( Ao)=…

Q: After 19 days have elapsed, 1/21 of a radioisotope sample remains undecayed. What is the half-life…

A:

Q: A moon rock collected by a U.S. Apollo mission is estimated to be 4.00 billion years old by…

A:

Q: What mass is lost over 24 hours of 1.8 * 1014 kJ/s of energy radiation?

A: Given data, the energy radiation = 1.8 * 1014 kJ/s and the time of mass lost = 24 hours = 24 * 60 *…

Q: An unknown radioactive element decays into non-radioactive substances. In 340 days the radioactivity…

A:

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: Co-60 is used extensively in radiotherapy as a source of y - rays. Its half-life is 5.27 years. a)…

A: Given, t1/2 = 5.27 years (a) The time required to decrease the activity by 35% of its original value…

Q: carbon-14 activity

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

Q: what is the half life of an isotope that decays to 25% of its original activity in 68.9 hours?

A: For a first order reaction, rate constant can be calculated as

Q: Ruthenium-106 (106Ru) is used to treat melanoma in the eye. This isotope decays by β– emission with…

A: In general, Number of proton is equal to the number of atomic number.The atomic number of is 44,…

Q: Cesium 137 is a commonly used isotope in the treatment of some cancers, someone you know may have…

A: The reactant given is Cesium 137 i.e 13755Cs.

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

A:

Q: When a radioactive isotope decays and the resulting isotope is also radioactive, it will decay, and…

A: a. Half-life of Rn-222 is 3.8 days.

Q: If 1.50 gram of a 2.00 gram sample of a radioactive substance undergoes decay in 60 minutes, then…

A:

Q: A 10.00-g plant fossil from an archaeological site is found to have a 14C activity of 3094…

A:

Q: A sample of wooden artifact is found to undergo 8 HC disintegrations per minute per gram of carbon.…

A:

Q: (28) An archaeologist claims that a bone in her collection is from a saber-toothed tiger that is…

A: we have to calculate decay rate of bone

Q: You are working as a technician in the radiology department of a large hospital. One of the…

A: The relation between activity, total time and half-life is shown below: