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How long will it take for a 64 gram sample to decay to 8 grams if the half life of the isotope is 5 hours?
Wiki User
∙ 14y ago
50 grams to 12.5 grams is a reduction of 0.75, or an ending amount of 0.25. That is two half-lives, or twenty years, in this case. The equation of half-life is ...
AT = A0 2(-T/H)
... where A0 is the starting activity, AT is the ending activity at time T, and H is the half-life at units of T.
Wiki User
∙ 12y ago
Wiki User
∙ 12y agoIf 64g has decayed to 8g, then 1/8 of the original remains. By inspection, you can see that three half-lives (1/2, 1/4, 1/8) have transpired. Divide 11.5 by three and you get 3.833 days.
Formally, the equation of half-life is ...
AT = A0 2(-T/H)
... where A0 is the starting activity, AT is the ending activity after some time T, and H is the half-life in units of T.
For the record, the official half-life of 86222Rn is 3.8235 days, by alpha decay, to 84218Po. For more information, please see the Related Link below.
Wiki User
∙ 14y ago0 - 5 hours : 64gr decay to 32gr
5 - 10 hours : 32gr decay to 16gr
10 - 15 hours: 16gr decay to 8gr
total : 15 hours
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If the half-life of a radioactive substance is 10 hours how long will it take for 50 percent of it to decay?
The half-life of a radioactive isotope is defined as the time taken for the isotope to decay to half of its initial mass. So to decay to 50 percent of its initial mass will take one half-life of the isotope. One half-life of the isotope is 10 hours so the time taken to decay is also 10 hours.
The half life of Rn-222 is 4 daysWhat was the original mass of a sample of this isotope remains after 21 hrs?
The half-life on 222Rn86 is 3.8235 days. A sample of this isotope will decay to 0.8533 of its original mass after 21 hours. AT = A0 2(-T/H) AT = (1) 2(-21/(24*3.8235)) AT = 0.8533
What is an atom's half-life?
The term half-life is one we apply to radioactive materials to talk about how quickly they decay. The half-life is the time it takes for half of a given sample of the unstable substance (whatever it may be) to undergo radioacitve decay. The way it works is quite simple, and though the numbers are statistically derived, they are pretty darn accurate. Let's look more closely.A sample of a radioactive nuclide (radiocarbon or carbon-14 for example) is made up of atoms with unstable nuclei. These nuclei will "fall apart" (decay radioactively) spontaneously, and each one can decay at any moment. What we don't know is when a givennucleus will decay. But if we watch a large number of these nuclei, we can count the decays across a period of time, and then come up with a rate of decay. We convert this into the length of time it takes for half of the given sample to decay. This length of time will be the half-life for that particular radionuclide. Each radionuclide has a unique half-life, as you might expect.A half-life is based on the decay rate of a particular isotope of a given element. It is a natural characteristic of that given radionuclide, and it is the amount of time it takes for a sample of it to decay to the point where half of it is gone and half the original sample remains. Use the links below to related questions to learn a little more.Drugs also have a half-life. Some drugs stay longer in the system, some disapate quickly. If the doctor wants to maintain a level of the drug in the body it maybe necessary to prescribe a dose every several hours or once or twice a day depending on how long the half-life of the drug is.From Wikipedia..The duration of action of a drug is known as its half life. This is the period of time required for the concentration or amount of drug in the body to be reduced by one-half. We usually consider the half life of a drug in relation to the amount of the drug in plasma. A drug's plasma half-life depends on how quickly the drug is eliminated from the plasma.Half life is the time duration in which half of the radioactive element would undergo decay. Suppose just for understanding purpose let us say half life is 3 hours.Say we have 4096 atoms freshNow after 3 hours half of this ie 2048 have got decayedIn the next 3 hours ie totally in 6 hours half of this ie 1024 would get decayed and 1024 would remainNow in the next 3 hours half of this ie 512 would get decayedIn the next 3 hours 256 and then 128, 64, 32, 16, 8 and so onBut in reality there would millions of atoms.
What is the half life of a radioactive substance if it takes 6 hours for 50 percent of it to decay?
That is the half-life - the 6 hours in this case.That is the half-life - the 6 hours in this case.That is the half-life - the 6 hours in this case.That is the half-life - the 6 hours in this case.
The half-life of a certain radioactive isotope is 12 hours If you start out with 10 g of the isotope after 1 day there will be?
If you take one day equal to 24 hours, then 1 day constitutes 2 Half lives. Mass of isotope left after 12 hours=10/2=5g Mass of isotope left after 2 half lives or 1 day=5/2=2.5g.
Determine the amount of time it takes for three fourths of a radioactive sample of an isotope of bromine to decay the half-life of the isotope is 16.5 hours?
About 33 hours
What is the amount of time it takes for three fourthsof a radioactive sample of an isotope of bromine to decay if the half life of the isotope is 16.5 hours?
It takes 2 half lives for an isotope to decay to 0.25 of its original value. If the half life is 16.5 hours, then 2 half lives is 33 hours. AT = A0 2(-T/H)
If the half-life of a radioactive substance is 10 hours how long will it take for 50 percent of it to decay?
The half-life of a radioactive isotope is defined as the time taken for the isotope to decay to half of its initial mass. So to decay to 50 percent of its initial mass will take one half-life of the isotope. One half-life of the isotope is 10 hours so the time taken to decay is also 10 hours.
The half life of Rn-222 is 4 daysWhat was the original mass of a sample of this isotope remains after 21 hrs?
The half-life on 222Rn86 is 3.8235 days. A sample of this isotope will decay to 0.8533 of its original mass after 21 hours. AT = A0 2(-T/H) AT = (1) 2(-21/(24*3.8235)) AT = 0.8533
What is an atom's half-life?
The term half-life is one we apply to radioactive materials to talk about how quickly they decay. The half-life is the time it takes for half of a given sample of the unstable substance (whatever it may be) to undergo radioacitve decay. The way it works is quite simple, and though the numbers are statistically derived, they are pretty darn accurate. Let's look more closely.A sample of a radioactive nuclide (radiocarbon or carbon-14 for example) is made up of atoms with unstable nuclei. These nuclei will "fall apart" (decay radioactively) spontaneously, and each one can decay at any moment. What we don't know is when a givennucleus will decay. But if we watch a large number of these nuclei, we can count the decays across a period of time, and then come up with a rate of decay. We convert this into the length of time it takes for half of the given sample to decay. This length of time will be the half-life for that particular radionuclide. Each radionuclide has a unique half-life, as you might expect.A half-life is based on the decay rate of a particular isotope of a given element. It is a natural characteristic of that given radionuclide, and it is the amount of time it takes for a sample of it to decay to the point where half of it is gone and half the original sample remains. Use the links below to related questions to learn a little more.Drugs also have a half-life. Some drugs stay longer in the system, some disapate quickly. If the doctor wants to maintain a level of the drug in the body it maybe necessary to prescribe a dose every several hours or once or twice a day depending on how long the half-life of the drug is.From Wikipedia..The duration of action of a drug is known as its half life. This is the period of time required for the concentration or amount of drug in the body to be reduced by one-half. We usually consider the half life of a drug in relation to the amount of the drug in plasma. A drug's plasma half-life depends on how quickly the drug is eliminated from the plasma.Half life is the time duration in which half of the radioactive element would undergo decay. Suppose just for understanding purpose let us say half life is 3 hours.Say we have 4096 atoms freshNow after 3 hours half of this ie 2048 have got decayedIn the next 3 hours ie totally in 6 hours half of this ie 1024 would get decayed and 1024 would remainNow in the next 3 hours half of this ie 512 would get decayedIn the next 3 hours 256 and then 128, 64, 32, 16, 8 and so onBut in reality there would millions of atoms.
Half of the radioactive atoms in a sample of sodium-24 will decay in 15 hours fifteen hours is the what of sodium-24?
By definition, halflife is the time during which half of the atoms originally present will undergo radioactive change. Therefore, after 15 hours, the number of atoms of Na24 remaining will be half the original number, 500; after an additional 15 hours, the number of atoms remaining will be 250, and after 45 hours the number remaining will be 125 (this is the answer). (Actually, 1000 atoms is too small a number for the halflife to be exactly manifested, but the earlier part of the answer assumes that it is.) so what he's trying to say is the answer is 125
How long does it take for 75 of an original 100 silver atoms to decay?
The decay rate of atoms is typically quantified by a half-life, which is the time it takes for half of the original atoms to decay. If we assume a constant decay rate, we can estimate that it takes approximately 3 half-lives for 75 of the original 100 silver atoms to decay. If the half-life of the silver isotope is 1 hour, then it would take approximately 3 hours for 75 of the atoms to decay.
How long will it take for a 12.0-g sample of iodine-131 to decay to leave a total of 1.50 g of the isotope The half-life of iodine-131 is 8.07 days?
half life is 8.1 days, so it takes 8.1 days for half the iodine sample to decay. It takes another 8.1 days for half of the remaining sample (ie. 1/4th of the original sample) to decay. So it takes 16.2 days for 3/4th of the sample to decay.
What is the half life of a radioactive substance if it takes 6 hours for 50 percent of it to decay?
That is the half-life - the 6 hours in this case.That is the half-life - the 6 hours in this case.That is the half-life - the 6 hours in this case.That is the half-life - the 6 hours in this case.
The half-life of a certain radioactive isotope is 12 hours If you start out with 10 g of the isotope after 1 day there will be?
If you take one day equal to 24 hours, then 1 day constitutes 2 Half lives. Mass of isotope left after 12 hours=10/2=5g Mass of isotope left after 2 half lives or 1 day=5/2=2.5g.
If a blood sample should be collected 2 hours postprandial when should the phlebotomist collect the sample?
2 hours after a meal.
The half-life of nicotine in the body is 2 hours. What is the hourly decay rate?
For hours?
