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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?
Wiki User
∙ 11y ago
the halflife is 10 days
Wiki User
∙ 11y ago
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A radioactive substance has has life of 5 days initial mass of 12kg how much the original isotope will remain after 10 days?
a radio active substance has half life of 5 days initial mass of 12kg.how much the original isotope will remain after 10 days?
How much of a radioactive substance remains after 10 hours if its half life is 5 hours?
Since half of the atoms of the original substance will have decayed after 5 hours, half of what is left will have decayed after the next five hours. The answer is 0.25 or one fourth of the original atoms will remain.
How much of a radioactive substance remains after 24 hours if its half life is 5 hours?
Using the formula Nt = N0*(1/2)t/t1/2 where Nt is the amount of stuff remaining after an amount of time, t, and t1/2 is the half-life, you get Nt = .036N0. So about 3.6% of the radioactive stuff is left.
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 does half-life of a radioactive sample mean?
A radioactive sample is constantly decaying. In the period of one half-life, 50% of the radioactive atoms are expected to decay to their stable fragments. After two half-lives, 75% of the radioactive atoms have decayed, and 25% of the original quantity remain.
The original sample of a radioactive substance?
Yes, and the question is ... ?
What is the half life of a radioactive substance that has changed through radioactive decay after 40 days the original substance left is one sixteenth of the original amount?
Let us use the expression = time duration = number of half lives x half life Given 40 = 4 x half life So half life = 10 days. Remaining = 1/16 = (1/2)4. So 4 half live have gone. If the number of half lives is n then (1/2)n would remain.
What types of elements are useful for dating materials?
Radioactive elements are used to date the age of rocks. Radioactive elements decay according to a known pattern. Scientists can use the elements of that pattern to determine when the rock with the original radioactive element was formed.
A radioactive sample has a half-life of 5.0 min What fraction of the sample is left after 20 min?
one sixteenth of the original
A radioactive substance has has life of 5 days initial mass of 12kg how much the original isotope will remain after 10 days?
a radio active substance has half life of 5 days initial mass of 12kg.how much the original isotope will remain after 10 days?
How much of a radioactive substance remains after 10 hours if its half life is 5 hours?
Since half of the atoms of the original substance will have decayed after 5 hours, half of what is left will have decayed after the next five hours. The answer is 0.25 or one fourth of the original atoms will remain.
What is the percentage of radioactive nuclei left after 3 half lives have passed?
12.5%
How is radioactive decay used to determine the absolute age a rocks?
The basic idea is to measure the amount of the radioactive isotope, and of one or more of its decay products. The older the rock, the larger the percentage of the original isotope that decayed - so the ratio between the original isotope and the decay product changes over time.
What is the problem with disposing of radioactive wastes is that they have a long what?
Radioactive substances have half-lives. This is because the isotope constantly is changing from the radioactive isotope to a daughter element. For example, eventually, when uranium's radioactivity is gone, it becomes lead. After one half life of a radioactive substance, only 50% of that substance is still radioactive. Therefore, after one half-life, a piece of uranium is 50% lead and therefore %50 less radioactive. After another half-life, it has 25% of the original radioactivity, and 75% of the original uranium has become lead. This is the problem with radioactive wastes. It takes many years just for one half lives for some substances, such as uranium. Because radioactivity is harmful, those substances have to be stored until they are no longer radioactive. So, in short, the problem with disposing of radioactive wastes is that they have long half-lives. (although this is not true with ALL substances because some have short half-lives, but, in general, radioactive substances have long half-lives.
How would martel quickly test the Powdery substance in the bowl to determine if it had properties similar to those of the original seawater?
color change
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.
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
