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Radioactivity
Page 8
Questions (537)
Iodine-131 has a half-life of 8 days. How many grams of a 12 g sample will remain at the end of 40 days?
how do i solve this? i
2 answers
asked by
jess
723 views
if you start with 150g of co-60 and 40 g remain, how much time has passed?
co-60 has a half lie of 5 yrs
1 answer
asked by
Logann
733 views
A 73-kg person is accidentally exposed for 215 s to a 16-mCi source of beta radiation coming from a sample of 14C.
What is the
1 answer
asked by
sara
731 views
Some radioactive nuclides have very short half-lives, for example, I-31 has a half-life of approximately 8 days. Pu-234, by
2 answers
asked by
kenzie
692 views
A 10 kg quantity of a radioactive isotope decays to 3 kg after 17 years. Find the decay constant of the isotope.
1 answer
asked by
Eric
688 views
The age of a bone was to be determined by 14C dating. 14C has a half-life of 5,730 years, and a Geiger counter shows that the
2 answers
asked by
Mike
714 views
what is the total mass of rn-222 remaining in an original 160g sample after 19.1 days?
1 2.5g 2 5.0 g 3 10g 4 20g how do you do
1 answer
asked by
John
652 views
A radioactive sample contains 2.45 g of an isotope with a half-life of 3.8 days. How much of the isotope in grams will remain
1 answer
asked by
Jacques
684 views
the half life radium-222 is 4 days. if a sample of radon-222 undergoes decay for 12 days, how much of the original parent
2 answers
asked by
Anonymous
663 views
A 71 mg sample of a radioactive nuclide is administered to a patient to obtain an image of her thyroid. If the nuclide has a
2 answers
asked by
Mr.Chemistry
672 views
The half-life of iodine -131 is 16 days. If you start with 100 gram sample, how many half-lives have past when you have less
2 answers
asked by
Taylor
668 views
If a 20 gram sample of a radioactive substance has a half-life of 6000 years, how many grams would be present after 18000 years?
2 answers
asked by
Owen
655 views
Sam is comparing the half-life of two isotopes of uranium. The half-life of Uranium-238 is 4.5×10^9 years. The half-life of
1 answer
asked anonymously
19 views
Po-218 is an alpha emitter with a half-life of 3.0 minutes. If a sample contains 42 mg of Po-218, how many alpha emissions would
2 answers
asked by
Mr.Chemistry
664 views
a radioactive substance decays 10% in 5 days. The amount remains after 20 days?
3 answers
asked by
koteswaramma
643 views
the process of radioactive decay is unpredictable and irreversible. which option would be an appropriate model of the
1 answer
asked by
haven
60 views
which statement best describes the effect of radioactive decay on a nucleus
the resulting nucleus is less stable that the
1 answer
asked by
haven
63 views
the half life of radium is 1600 years of 100 grams of radium existing now 25 grams will remain after how many years
2 answers
asked by
Anonymous
636 views
if the amount of radioactive iodine-123 in a sample decreases from .400g to .100g in 26.2 hours, what is the half-life of
2 answers
asked by
j
623 views
The mass of a radioactive substance decreases at a rate proportional to the mass at the time. The orginal mass is 700 grams and
2 answers
asked by
Kelly
622 views
The disintegration of a radioisotope, such as I-131 to Xe-131, is another example of a first-order reaction.
It has a half-life
3 answers
asked by
Ashley
641 views
A 10 kg quantity of a radioactive isotope decays to 3 kg after 17 years. Find the decay constant of the isotope.
1 answer
asked by
Eric
639 views
If a radioactive isotope has half life of 5 days,how long will it take for its radioactive strength to be a maximum of one
2 answers
asked by
Bree
629 views
experiments show that radium disintegrates at a rate proportional to the amount of radium present at the moment . if half life
3 answers
asked by
NOEL
623 views
After 1.84 days, the activity of a sample of an unknown type radioactive material has decreased to 85.8% of the initial
2 answers
asked by
andrew
618 views
The strontium-90 isotope decays by the reaction below. It has a half-life of 28 yr. If the initial activity of this isotope was
2 answers
asked by
Morgan
614 views
The half life of the radio active substance is the time require the half the substance to decay. the mount A ( in grams) of 100
2 answers
asked by
sai
610 views
Cobalt-60 is radioactive isotope used to treat cancers. A gamma ray photon emitted by this isotope has an energy of 2.13 x
2 answers
asked by
John
611 views
Suppose you have 100 g of radioactive plutonium-239 with a half-life of 24,000 years. How many grams will remain after (a)
2 answers
asked by
b
607 views
If a radioactive isotope has a half-life of 20 hours, how many half-lives have occured after 80 hours have passed?
a. 5 b. 4 c. 2
1 answer
asked anonymously
40 views
The half-life of a certain radioactive material is 42 days. An initial amount of the material has a mass of 49 kg. Write an
1 answer
asked by
Cassira Lauf
77 views
How many half lives will it take for a sample of a radioactive isotope containing 20000 radioactive nuclei to decay to 2000
3 answers
asked by
Dianne
613 views
A certian radioactive isotope has a half-life of 1 hour. If you start with 1 gram of the material at noon, how much of the
5 answers
asked by
Judy
611 views
When a parent radioactive nucleus splits by ejecting an alpha particles (two protons and two netutrons), the
remaining nucleus
4 answers
asked by
pam
600 views
iodine 131 has a half life of 8 days. If 5 mg are stored for a week, how much is left? How many days does it take before only 1
2 answers
asked by
shannon ortiz
561 views
The number of radioactive nuclei present at the start of an experiment is 3.27 x 1015. The number present twenty days later is
2 answers
asked by
james
570 views
It took 109.8 years for a 300.0 mg sample of an unknown radioactive material to completely disintegrate. Calculate the mass of
2 answers
asked by
Anonymous
567 views
What happens to the mass of a sample containing a radioactive element during its half-life?
A. The mass decreases by half. B. The
3 answers
asked by
Kalie
579 views
Cobalt-60, which undergoes beta decay, has a half-life of 5.26 yr. How many beta particles are emitted in 190s by a 3.10mg
2 answers
asked by
Steven
572 views
Technetium-99m is an ideal radioisotope for scanning organs because it has a half-life of 6.0 {\rm hr} and is a pure gamma
2 answers
asked by
Shay
589 views
A radioactive material has a half life of 500 years.
A) Given 20 grams of this material, how much will remain after 1,000 years?
2 answers
asked by
Milly
560 views
A particular radioactive substance has a half-life of 4 minutes. How long will it take for 250 g of this radioactive material to
2 answers
asked by
Anonymous
569 views
Suppose that you start with 1000000 atoms of a particular radioactive isotope. how many half-lives woruld be required to reduce
2 answers
asked by
Shay
580 views
What are the various uses of radioactivity in healthcare? What are the future trends in healthcare with respect to the use of
2 answers
asked by
ROCKY
563 views
I have tried for days to figure out how to work this problem. Please help show me how to find the answer.
A particular
2 answers
asked by
Tina
548 views
a radioactive sample has a decay rate R of 518 decay/min at time t=7 min and 156 decay/ min at time t=17 min. calculate the
3 answers
asked by
renaa
545 views
A material has 32 atoms in all; 24 decayed and the rest undecayed. If the half-life of the radioactive material is 1000 years,
5 answers
asked by
Angie
558 views
Marie Curie first identified the element radium in 1898. She found that the radium-226 (mass 3.77x10^-25 kg) decays by emitting
3 answers
asked by
Amber
544 views
The half life of an element Z is 10days. if there are 10g of Z intially, what will be its mass after 40 days?
3 answers
asked by
Deborah
526 views
A 10 kg quantity of a radioactive isotope decays to 3 kg after 17 years. Find the decay constant of the isotope.
2 answers
asked by
Eric
542 views
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