one of several states of a chemical element differing only in the number of neutrons present in the nucleus.
3
votes
1answer
53 views
Why does the metastable form of Technetium-95 have a longer half-life than its most stable state?
I was looking at the isotopes of technetium page on Wikipedia recently, and it seems that the metastable ${^{95m}Tc}$ has a substantially longer half-life (61d) than its most stable state of ...
1
vote
1answer
28 views
Isotope exchange between heavy water and plastic container
It is known that pure heavy water will quickly get contaminated by light hydrogen atoms if exposed to air due to isotope exchange.
Does the same thing happens when heavy water is stored in plastic ...
0
votes
2answers
225 views
Is it possible to speed up radioactive decay rates? [duplicate]
Possible Duplicate:
Do some half-lives change over time?
Would it be possible to considerably speed up the decay rate of an isotope?
Considerably meaning more then a 1 or 2% increase in ...
0
votes
0answers
28 views
Energy of split of nucleus [closed]
How much energy must be supplied to the nucleus of lithium isotope Li-7 (3 protons, 4 neutrons) to separate them into individual protons and neutrons? The atomic weight of lithium is $1.1524 \times ...
11
votes
1answer
693 views
Why is technetium unstable?
Is there a simple account of why technetium is unstable?
From the Isotopes section of Wikipedia's article on Technetium:
Technetium, with atomic number (denoted Z) 43, is the lowest-numbered ...
2
votes
0answers
74 views
The force exerted by a ~10 Tesla magnet on a C13 isotope?
How much force would a ~10 Tesla magnet exert on a weakly magnetic C13 isotope? If I made a molecule of diamond with $N$ C13 atoms, how large would $N$ need to be for me to pull on it with something ...
4
votes
2answers
168 views
Is there a direct relationship between an isotope's neutron count and radioactivity?
In my textbook, it lists isotopes of Carbon: C-12, C-13, and C-14. It noted that C-14 is radioactive (C-12 and C-13 are not).
Is there a direct relationship between the number of neutrons and an ...
2
votes
1answer
212 views
Unknown isotope
Problem description:
The most common isotope of a single nucleus stripped of its electrons is accelerated through a potential difference of 1225V and fired horizontally into a B-field directed ...
1
vote
2answers
206 views
Is it viable to convert nuclear waste into safe isotopes?
I read that powerful pulsed lasers can change isotopes:
J. Magill, et. al.: "Laser transmutation of iodine-129".
Did anyone estimate what would be the energy costs to transmutate 1 kg of fission ...
4
votes
1answer
292 views
Dangerous dose of I-131?
I was searching a lot and could only find dosages for curing cancer and allowed emission, but no Iodine-131 dose that could be connected with increased thyroid cancer risk (like, 10mSv is the ...
1
vote
2answers
218 views
Isotope properties plotting tool?
I'm looking for something that will generate scatter plots comparing different properties of isotopes. Ideally I'd like some web page that lets me select axis and click go but a CSV file with lost of ...
10
votes
3answers
764 views
Why some nuclei with “magic” numbers of neutrons have a half-life less than their neighbor isotopes?
It's easy to find the "magic" numbers of neutrons on the diagrams of alpha-decay energy: 82, 126, 152, 162. Such "magic" nuclei should be more stable than their neighbors.
But why some nuclei ...
2
votes
1answer
211 views
Obtaining isotope stability
For a given isotope, one can obtain the binding energy using the semi-empirical mass formula.
For example, has a binding energy of 1782.8 MeV. From this information, how can the likelihood of the ...
