Questions tagged [isotope]
This tag should only be applied where the effects are specifically related to variance in mass number with the same atomic number (existence of isotopes). Examples include: radioactivity and other nuclear properties, kinetic effects, specific relevance to spectroscopy (e.g., NMR, IR), isotope separation, isotopic analysis.
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Mapping of half-life decay for all elements/isotopes
Is there an open resource that helps illustrate all paths of decay for all isotopes (e.g. $\ce{^{99}Mo}$ decaying to $\ce{^\mathrm{99m}Tc})?$ I know the result state/transition map would be massive, ...
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Normalising Kinetic Isotope Effect Per Deuterium Atom
I've synthesised a protic and deuterated version of a specific molecule where there are two deuterium atoms in the latter. I then go about and measure the kinetic isotope effect (KIE) for a reaction ...
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Is it possible to estimate how much Plutonium existed during the earth's formation?
Plutonium is a man-made element, but minute quantities of it exist on earth. It's probable the earth had much larger quantities of it during its formation as a planet, but most of it decayed due to ...
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How much D2O is in Vienna Standard Mean Ocean Water?
I'm curious how much $\ce{D2O}$ (heavy water) is in Vienna Standard Mean Ocean Water. I am interested in $\ce{D2O}$ molecules and not $\ce{HDO}$/$\ce{D+}$/ $\ce{DH2O+}$/$\ce{D2HO+}$/$\ce{D3O+}$ or any ...
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Isotope labeled experiment analysis
I'm analyzing a dataset generated with LC-MS from cells that were fed $\ce{^13C}$-Glucose. There are 3 groups in total each with a different media conditions. My goal is to identify differences ...
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How to define the reduced mass for estimating Kinetic Isotope Effects
I am trying to think about radical reactions using zero-point energies (from the harmonic oscillator model). I have read that substitution of a bond with isotopes can alter the rate of a reaction.
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The isotopic effect in chemical kinetics
I conducted a chemical experiment (degree in chemical engineering) to understand the isotopic effect in chemical kinetics. In the experiment, I reacted isopropanol and D-isopropanol (D stands for ...
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Bond frequency vs Bond Strength in Kinetic Isotope Effect
I am confused by the following: in Ansyln's Modern Physical Organic Chemistry, a higher vibrational frequency defines a stronger bond due to the deeper/sharper potential well (page 76). However, the ...
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Mass spec mass calculation difference
This is not a homework question, but for research.
I am performing mass spec on serum metabolites using Thermo Q Exactive PLUS with a HESI source which was set to a spray voltage of -2.7kV under ...
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isotopic composition database for carbon isotopes
I am seeking an isotopic composition database for carbon isotopes, since I would like to make a figure showing the different isotopic compositions of different materials. The best woudl be if the ...
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Classic/killer/easy application for the deuterium kinetic isotope effect?
I'm a physicist. While visiting someone's o-chem class I learned about the existence of the deuterium kinetic isotope effect. This seems like an extremely sweet example of zero-point energy, and I ...
user6999
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What is mass-independent isotope separation/fractionation?
How can any separation/fractionation of isotopes be mass-independent, if the only difference between two isotopes is mass?
The only clue(s) on Wikipedia mention molecular symmetry, 'forbidden' spin-...
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2 modes of radioactive decay for hydrogen-5?
While looking at a table of helium isotopes it said that helium-8 turns into Tritium(hydrogen-3) and helium-5 through fission and beta decay.
But the pathway to helium-5 isn't so direct. It is more ...
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Electron affinity of isotopes anomaly
According to the Wikipedia article the electron affinity of $\ce{^{2}H}$ is higher than the electron affinity of $\ce{^{1}H}$ however the electron affinity of $\ce{^{18}O}$ is lower than $\ce{^{16}O}$....
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Can deuterium be separated from heavy water via electrolysis? It is an isotope of hydrogen, so I guess it should act in the same way?
I was wondering if it is possible to separate deuterium from heavy water via electrolysis.
Also, is this the way deuterium gas is obtained on an industrial scale, or are there better methods?
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Where do the electrons for which RTG's use for the Seeback effect come from?
I know that RTG's use Radioactive Isotope that emit Alpha particles generally (ie. NASA uses Pu 238), I also know that these Alpha particles are consiting of 2 Protons and 2 Neutrons, since the RTG ...
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Why do foraminifera use less magnesium in their shells when the water is cold?
When scientists study ancient seabed cores, they say they can judge the temperature of the water in the past by analyzing the magnesium to calcium ratio in foraminifera shells (both in the form of ...
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Effect of pH on sulphur isotope variation on a landscape
I recently ran a forest regression model, this model showed me that increasing soil pH increases sulphur isotope variation across the landscape. I am not how this is possible and if it makes sense
