Questions tagged [isotopes]
The isotopes tag has no usage guidance.
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Finding exhaustive list of isotopes known to have the induced-fission property [closed]
Not sure if this is the right place to ask, since I am looking for help finding information.
I am making course material in low level nuclear physics. For this, I've created my own visual Segre Chart (...
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U-235 percentage in nature
It is mentioned everywhere that the percentage of Uranium 235 isotope found in natural uranium is 0.711%. Samples collected from ores around the earth also seem to attest to this claim.
Is U-235 0.711 ...
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Capillary action for isotope separation
Take, for example, D2O and H2O. As they have different densities, they should have a different maximum capillary height h, where h is defined according to Jurin's law. Then, each isotope of D and H ...
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How the $N/Z$ ratio affects the stability of isotopes and their method of radioactive decay?
Although there is a graph that tells us the number of isotopes and which ones are stable or abundant in nature, like the one below, I have come across the $N/Z$ ratio, which is the number of neutrons ...
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Water molecule formed by at least one tritium atom
If a water molecule is made up of at least one tritium atom, when the tritium atom(s) decay radioactively, what happens to that water molecule? Does it bond to one or two Helium atoms? Is there any ...
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If I sent a sample of U238 to the upper atmosphere
If I sent a sample of U238 to the upper atmosphere, would the solar gamma rays be sufficient enough to cause photodisintegration and the subsequent production of Np237?
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What is the half-life of deuterium if protons decay?
If we where to assume that protons decay and we know the half-life of protons, would it be possible to determine the half-life of deuterium?
If $^{1}$H (a single proton) has a half-life of, say, $10^{...
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Are their pairs of Nuclear Isobars that differ in energy by less then the Lighter Nuclides Characteristic X-ray?
Isobars are atoms (nuclides) of different chemical elements that have the same number of nucleons.
According to the https://en.wikipedia.org/wiki/Mattauch_isobar_rule if you have two adjacent elements ...
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Potential yields of Np-237 using a synchotron
U238 releases a neutron when it is exposed to photons of around 11 MeV, and the resulting U237 promptly decays into the fissile Np237.
In such a situation, what equations can I use to relate the ...
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Is there a way to determine whether a given nucleus is radioactive?
When a nucleus decays it is finding a more stable configuration, as all nature is. But is there a way of finding whether a specific configuration will decay?
I know that there is a specific proton-to-...
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Can moscovium-299 exist and is it possible to predict how stable it will be?
Five isotopes of element 115 (moscovium) have been created in the laboratory with atomic weights ranging from 286 to 290, each having a progressively longer half-life, ranging from 20ms to 650ms: ...
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Why is U-238 detrimental for nuclear bomb？
I know U-238 is more stable than U-235, because it is an even-even nucleus. Only neutron with energy larger than 1.6Mev can split an U-238, while any neutron can split U-235.
But why is the presence ...
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Raman Rotational Effect for Diatomic Molecules
I have a doubt about Rotational Raman effect phenomena. As we know for Rotational effect the heavier of the two isotopes the band levels goes down between the two (which is most heavy).
So say for H2 ...
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Are very stable super-heavy elements theoretically possible?
I was recently reading about superheavy elements.
According to that article all superheavy elements currently known have only been synthesized in laboratory experiments and have a very short half-life,...
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How much $\rm D_2O$ is in Earth's icepacks? [closed]
How much $\rm D_2O$, by mass and/or percentage, is locked in Earth's polar icepacks? Is the $\rm D_2O$:$\rm H_2O$ ratio the same as elsewhere?
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Salt $\rm NaCl$ at the epicenter of a nuclear explosion [closed]
As is known, in the case of neutron irradiation, sodium is converted into the unstable isotope Na-24.
This isotope is terribly radioactive. And in the event of a nuclear strike on a salt mine or ...
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Why is the deuterium bottleneck temperature 0.1 MeV?
During big bang nucleosynthesis (BBN), deuterium has a lower binding energy per nucleon (~1.1 MeV) than the other similar nuclei, and so prevents heavy elements from forming until the temperature ...
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Non-irradiative methods to create radioactive isotopes?
My understanding is that the primary methods with which one can create a radioactive isotope are 1) just waiting for the isotope you want (by means of nuclear decay), or 2) some kind of induced ...
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If there wasn't a weak nuclear force, what would be the heaviest stable theoretically stable isotope with equal protons and neutrons?
If there was no weak nuclear force, what would be the heaviest stable theoretically stable isotope with equal protons and Neutrons? For our universe the heaviest such isotope is calcium 40, but most ...
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Why is Astatine-210 (At-210) the longest-lived isotope of astatine despite possessing an odd number of neutrons?
I am guessing that isotopes with an even number of neutrons more readily release an alpha particle... When and if At-210 does that, it still has the problem of being 'odd/odd'...
But this begs the ...
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Which proportions of deuterium and tritium did the National Ignition Facility's hohlraum contain?
The National Ignition fusion recently announced the achievement of nuclear fusion "ignition", i.e. more energy released from a sample undergoing nuclear fusion reactions than was directly ...
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Why do magic number nuclei have higher first excitation energies?
I have read online that one property of stable 'magic number' nuclei is that they have higher first excitation energies. Why is this?
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Why does the doubly-magic nucleus tin-$132$ have such a short mean lifetime?
Why does the doubly-magic nucleus tin-$132$ have such a short mean lifetime? Only because it is far from valley of stability?
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Does a charged isotope have a different half life than the neutral counterpart?
Let's say you have a radioactive isotope of an element with relatively short half-life (e.g. <0.5s).
If you add or remove electrons from the atom so that is has a positive or negative charge, is ...
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Could there be undiscovered long-lived isomers of unstable elements?
There are 80 stable elements in the periodic table. These elements have at least one stable isotope. Other elements don’t have any identified stable isotopes. The existence of stable isotopes can be ...
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Why isn't lead-207 radioactive?
I've recently learnt from here, in an atom, the stability of an atom is described in two contexts, one according to the ratio of neutron and proton of the atom. The ratio will always be between 1 and ...
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Why is $^{58}\rm Ni$ the most common isotope or nuclide of nickel if $^{62}\rm Ni$ has the most binding energy (per nucleon) of ANY known nucleus?
Nickel-58 and nickel-62 are four neutrons apart, not even just two, so this fact is especially confusing to me...
I have read about how nickel is synthesized in stars from silicon, so this is perhaps ...
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Why is there a sudden drop-off in half-life of isotopes at around 130 neutrons? Is there a name for this?
Pertaining to the chart of nuclides, there is a region above Bismuth, in which the relatively continuous trend of stability is interrupted by a batch of isotopes all with extremely short half-lives. I ...
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In the event of a disaster at any nuclear power plant other than Chernobyl, would we be dealing with the emission of radioactive iodine isotopes?
Would any nuclear catastrophe emit radioactive iodine isotopes?
Do some power plants have different cores that would emit other radioactive isotopes but not iodine isotopes?
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Why does a tritium nucleus have a higher mass than $^3\rm He$?
$^3\rm He$ has a lower (nuclear) mass than tritium which is why the latter decays into the former. This is not explained by the semi-empirical mass formula, which would predict a lower binding energy (...
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General Half-life calculation for an abitrary nucleus
I have been getting back into physics and I was wondering whether there was a generalized half-life equation for any given nucleus composition.
For instance for gold isotope 210-AU. Is it possible to ...
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Would isotopes of hydrogen separate in liquid phase?
According to https://www.aqua-calc.com/calculate/volume-to-weight
the difference in density of deuterium/hydrogen in liquid state is 70miligrams/cm^3 vs 169miligrams/cm^3.
Would this be a sufficient ...
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Easy question regarding RF and ion traps
I saw this interesting video:
https://www.youtube.com/watch?v=d-qTa_7FtAA
In this video, from the 8:55 mark to 11:55, this man explains using unique frequencies for each element(?) with a unique m/z ...
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Why $\rm Ag$ 108 decays into $\rm Cd$ 108 most of the time?
In the table of nuclides, it shows that $\rm Ag$ 108 can go through either electron capture or beta- decay (though the branching ratio for electron capture decay is much lower). What determines that? ...
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Examining isotope shift in ions vs neutral atoms - why use ions?
I'm currently deep-diving isotope shift (IS) spectroscopy literature. I've come across several papers that look at the isotope shifts of charged ions, and I want to try and understand why researchers ...
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Does each spectral line of an atom/molecule have a unique lineshape?
A spectral line is determined by a particular transition in an atom or molecule. In reality, this line isn't infinitely sharp, but has a small distribution about the resonance frequency as a result of ...
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How can negative beta-decay energy be negative?
The International Atomic Energy Authority (IAEA)'s Nuclear Data Services list tables of nuclear data, including a table of atomic masses and beta decay energies, data taken from Huang et al., Chin ...
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Why are fermionic atoms less prevalent than bosonic ones?
Many atoms have no stable fermionic isotopes. Those that do typically have more stable bosonic isotopes than fermionic ones. Furthermore, the fermionic isotopes of most atoms are lower in natural ...
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If plutonium-238 (Pu-238) absorbs a neutron, does it become Pu-239?
I am asking this simple question because I am always hearing about how thorium reactors are less perilous to the world because, unlike uranium reactors, they produce some Pu-238, which is not suitable ...
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What determines the half-life (or stability) of an isotope?
Why is it that some elements do not have any stable isotopes, while others of very similar mass have multiple stable isotopes? What determines this phenomenon and what determines the strict ...
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How can I determine if an element undergoes electron or positron emission?
I'm not sure how I can determine whether an element has $\beta^-$ or $\beta^+$ emission, or no $\beta$ emission at all.
I'm told that positron decay happens when there are too many protons and not ...
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Is there an online resource for fusion outcomes of various elements at various energy levels?
I'm looking to find a chart of nuclides, their potential fusion products and measured energy levels, in a similar vein as NuDat 3, but for fusion.
It doesn't need to be cleanly formatted like NuDat, ...
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Isotope that decays when ionized
Some time ago, I read about a certain isotope that is stable when neutral but decays with electron emission (beta) when being completely ionized, but I can't find which one it was.
Which isotope ...
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What are the chemical properties of uranium-233 that makes it a more efficient fuel than uranium 235?
i'm trying to find what the best nuclear fuel would be. I've already tried finding this answer online but there's nothing that helps. i would like to find an answer please. btw, by efficient, i mean ...
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Can the Schrödinger equation be solved for deuterium?
Or does the added neutron complicate things too much?
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Does every element have a half-life?
Will every element slowly decay into something else? Or do some isotopes have infinite half-lives?
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Why do different atomic isotopes have different atomic spectrums?
We know that different elements have different atomic spectrums as a result of the difference in charge and electron shielding that occurs when extra protons are added to a nucleus.
We also know that ...
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Why are lithium-$7$ and boron-$11$ respectively more abundant than lithium-$6$ and boron-$10$?
Lithium, beryllium and boron are unusually low in abundance for low-$Z$ elements, because their stable isotopes aren't the ones stellar nucleosynthesis makes without consuming them. What little ...
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Question about potential additives to a very relative Covid 19 m R N A patent (i.e. radio active Ions: Iodine 125 or 131, Strontium 89, cesium, etc.) [closed]
I am a genuinely concerned citizen with barely any scientific background concerning radioactive isotopes. However, I have a question about items listed in an mRNA 1273 patent on Moderna's website.
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Stable nuclear isotopes
It appears that all stable nuclei may be seen to be composed of pairs of smaller, stable nuclei, e.g., the Li-7 nucleus seemingly is composed of H-3 and He-4, i.e., 1(3) + 2(4) -> 3(7). What if any ...
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