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There was a sample of 700 milligrams of a radioactive substance to start a study. Since then, the sample has decayed by 8.8% each year?
Let t be the number of years since the start of the study. Let y be the mass of the sample in milligrams. Write an exponential function showing the relationship between t and y.
JaeLyn Ross
hydroxides
Mertie Ferry
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What must be true for radioactive dating to be possible with a certain sample?
The sample must contain radioactive elements.
What does the half life of a radioisotope correspond to?
The length of time required for half of a sample of radioactive material to decay
What percentage of a radioactive sample remains after 5 half-lives?
3.1 %
Determine the amount of time it takes for three fourths of a radioactive sample of an isotope to decay?
The half-life is 4 days. That means half of it will be gone in 4 days, and that leaves half of the original sample. In another 4 days, half of the remaining half will have decayed. And that will leave only 1/4 th of the original sample. That means 3/4 ths of the original sample will have decayed. In 8 days, three fourths of a sample of a radioactive element with a half-life of 4 days will have decayed.
Is it true that the density of a substance is the same for all samples of the substance?
No, as density also depends on the state of matter in the sample of the substance.
The original sample of a radioactive substance?
Yes, and the question is ... ?
A sample of a radioactive substance decayed to 95 percent of its original amount after a year.what is the half life of the substance?
The half-life of a radioactive nuclide when 95% of it is left after one year is 13.5 years. AT = A0 2(-T/H) 0.95 = (1) 2(-1/H) ln2(0.95) = -1/H H = -1/ln2(0.95) H = 13.5
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.
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 do we call the time it takes for half of a radioactive sample to decay?
The time it takes for half of a sample to decay is called the "half-life" of the corresponding material.
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.
What must be true for radioactive dating to be possible with a certain sample?
The sample must contain radioactive elements.
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.
How much of a 100-g sample of thorium-234 will be unchanged after 48.2 days?
25 gExplanation:Think about what a nuclear half-liferepresents, i.e. the time needed for an initial sample of a radioactive substance to be halved.
How much of radioactive substance remains after 15 hours if it's half life is 5 hours?
The half-life of a radioactive substance is the time that it takes for half of the atoms to decay. With a half-life of 10 days, half has decayed in this time. After 20 days, a further 10 days/another half life, a further half of the remainder has decayed, so 1/4 of the original material remains, 1/4 of 15g is 3.75 grams. This is the amount of original radioactive substance remaining, but it’s daughter isotope ( what the decay has produced ) is also present, so the original sample mass is effectively constant, especially in a sealed container. Even in an unsealed container, and assuming alpha ( helium nucleii) emission, a drop in mass per radioactive atom of 4 Atomic Mass units, compared with the original atom of, say 200 amu is only 2% mass decrease, less for heavier decaying nucleii.
How long will it take half of a radioactive sample to decay?
The length of time depends on the element and isotope, but the point at which half of the sample has decayed is known as the half-life.
How does a sample of radioactive waste decay to a nonhazardous level?
All radioactive material has a characteristic half-life. This is a period during which half the matter from the original mass will have decayed into a daughter element. Either the daughter element is non-radioactive and therefore non-hazardous or it is radioactive and has its own half-life. The total radioactivity thus reduces over time and at some stage is deemed to reach a non-hazardous level.
