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A radioactive sample has a half-life of 5.0 min What fraction of the sample is left after 20 min?
Wiki User
∙ 14y ago
one sixteenth of the original
Wiki User
∙ 14y ago
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What fraction of the radioactive atoms currently present will be left after four minutes if a sample of gas has a half life of two minutes?
200
What fraction of a radioactive sample decays after three half lives?
If I take a radioactive sample of 400 moles of an unknown substance and let it decay to the point of three half-lives I would have 50 moles left of the sample. 1/2 of what is left will decay in the next half-life. At the end of that half-life I will have 25 moles left of the unknown substance or 4/25.
A particular element has a half life of 27 daysafter 54 days how much of the radioactive material is left?
The half life is the time it takes for half the atoms in a given sample to decompose. Knowing this then after 27 days there is half the amount left. After 54 days then there is half that half left so that's a quarter.
How can a half-life be used to tell the age of a sample?
The half life of a radioactive substance is the time it takes for half of that substance to undergo radioactive decay. In some substances, like carbon 14, the proportion of it in a living being can be estimated, so the amount of it left in a sample correlates to the time since that sample was alive. Other substances, like, for example, Potassium 40, decays into Argon 40. The ratio of K40 to Ar40 in rock samples gives the age of some igneous rocks.
Is the atom left after decay often radioactive?
Truw
What fraction of the radioactive atoms currently present will be left after four minutes if a sample of gas has a half life of two minutes?
200
What happens to a radioactive material over time?
It disintegrates into its daughter nuclei that are much more stabler than the radioactive nuclei. If a sample of radioacictive material is left it will decay into another element over a period of time. Note that complete decay is not possible. A fraction of the original radioactive material will always remain in the sample.
What fraction of a radioactive sample decays after three half lives?
If I take a radioactive sample of 400 moles of an unknown substance and let it decay to the point of three half-lives I would have 50 moles left of the sample. 1/2 of what is left will decay in the next half-life. At the end of that half-life I will have 25 moles left of the unknown substance or 4/25.
How do you determine the half life of a radioactive substance that has changed through radioactive decay After 40 days the original substance left is is one sixteenth of the original amount?
the halflife is 10 days
How much of the original sample will be left at the end of the second day if a sample of radioactive isotope has a half life of 1 day?
Hi, Each half-life means the mass of the sample has decreased by 1/2 its mass. Thus; After 1 half-life, 1/2 the sample has decayed. After 2 half-lives 3/4 of the sample has decayed. Hope this helps.
A sample of radioactive isotope has a halflife of 1 day how much of the original sample will be left at the end of the fourth day?
If a sample of radioactive material has a half-life of one week the original sample will have 50 percent of the original left at the end of the second week. The third week would be 25 percent of the sample. The fourth week would be 12.5 percent of the original sample.
How much radioactive sample will be left at the end of two weeks?
That would depend on the initial amount of the substance, as well as on its half-life.
What is the longest radioactive halflife?
First, it isn't very accurate to talk about a radioactive "element"; you should talk about radioactive isotopes. Different isotopes of the same element can have very different behavior in this sense. For example, hydrogen-1 and hydrogen-2 are stable, while hydrogen-3 is not (half-life about 19 years).Individual atoms, in a radioactive isotope, will decay at a random moment. The half-life refers to how long it takes for half of the atoms in a given sample to decay (and convert to some other type of isotope).
What happens during radioactive dating?
Radioactive dating is carried out with substances which were formed at some unknown point in the past and contained a known proportion of a radioactive isotope of some element. Radioisotopes decay into other elements at a fixed and known rate. So, if you know how much of the radioactive isotope is still left in the sample, then you can work out how long it would have taken for the rest to have decayed into other elements. That gives the age of the sample.
If a radioactive material has a half-life of 10 years what fraction of the material will remain after 30 years?
One eighth would be left.
What is the difference between radioactive decay and radiometric decay?
It is the difference between sand running out of an hour glass and determining what time it is by how much sand is left. Radioactive decay happens at a steady rate. If you can determine how much of that radioactive isotope ought to have been in a sample at the start and you can measure how much is left, you can tell how much time has passed.
What is the difference between radioactive decay and radiometric dating?
It is the difference between sand running out of an hour glass and determining what time it is by how much sand is left. Radioactive decay happens at a steady rate. If you can determine how much of that radioactive isotope ought to have been in a sample at the start and you can measure how much is left, you can tell how much time has passed.
