Questions tagged [nuclear]

For questions relating to the dynamics and processes that occur within and interactions between the nuclei of atoms.

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51
votes
5answers
10k views

The last element's atomic number

I was just thinking what can be the last atomic number that can exist within the range of permissible radioactivity limit and considering all other factors in quantum physics and chemical factors.
12
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1answer
716 views

How is the electron “trapped in the crystal” in irradiated NaCl?

Pennsylvania State University provides irradiated $\ce{NaCl}$ (180,000 rads of gamma radiation) to teachers for a very entertaining demonstration. The salt is orange after irradiation. When it is ...
11
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0answers
145 views

What happens when para-water ice is suddenly melted?

Background (hydrogen) In the case of recently liquified hydrogen (which is quite cold of course) it must be re-equilibrated before loading on to a rocket as fuel to avoid a sudden exothermic ...
10
votes
1answer
6k views

Why can't light pass through a gold foil, but alpha particles can?

Rutherfords experiment showed that most of the alpha particles passed through a thin gold foil undeflected. So why can't light pass through the foil, which is supposedly thinner than the heavy alpha ...
7
votes
1answer
275 views

Molecular Hamiltonian of Helium hydride ion

Currently, I am going through Quantum Simulation of Helium Hydride Cation in a Solid-State Spin Register. I am not a chemist but rather a computer scientist hence having trouble following the paper. ...
6
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3answers
885 views

Understanding Beta Decay

Reading Wikipedia on "Beta Decay" they list the equation of Carbon-14 decaying into N-14. see equation https://en.wikipedia.org/wiki/Beta_decay I presume the 14 refers to total protons and neutrons. ...
6
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4answers
38k views

Nuclear fusion reactions violate law of conservation of mass, but it has not yet been taken into account. Why?

According to the law of conservation of mass, during any physical or chemical changes, the total mass of the products is equal to the total mass of the reactants. But in nuclear fusion reaction if ...
6
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1answer
90 views

Interpret Radiodecay Symbolism

$\binom{16}{8}$O (n,$\alpha$)$\binom{13}{6}$C and $\binom{9}{4}$Be ($\alpha$,n)$\binom{12}{6}$C I had initially thought the products & reactants may be O-16 $\to$ C-13 + He-2 + p$^+$ from alpha ...
6
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2answers
158 views

Radiation time vs. half life period

Is radiation time the same thing as half life period? Also, if I'm talking about excited species in a gas, how would the gas interaction affect the radiation time, are there some formulas/approaches?...
6
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2answers
2k views

What chemical elements does a nuclear explosion release into its mushroom cloud?

I'm interested in the mushroom cloud produced by a nuclear explosion: What is it made of? I know that the uranium fission reaction is the following (from this web page) $$\ce{{}^{235}U + {}^1_0n -&...
5
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3answers
1k views

How are nuclei stable?

We all know that the density of the nucleus is very high. Nuclei are made up of protons and neutrons, and while protons have the same charge, they are closely packed in a nucleus. How does the ...
5
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1answer
753 views

Are photons ejected from atomic nuclei?

I have heard that electrons absorb or eject photons when transitioning from one orbital to another. Is this correct? Can atomic nuclei eject photons?
5
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1answer
565 views

How to derive the nuclear spin of 23Na?

Is it possible to derive the nuclear spin I=3/2 for $\ce{^23Na}$ from a term scheme or from something else from spectroscopy? I thought the nucleus spin is empirical (and cannot be calculated from J ...
5
votes
1answer
471 views

Why do Alpha particles not collide with electrons during alpha decay? [duplicate]

Alpha particles are positively charged, so my question is that during alpha decay, when these are released from the nucleus, why doesn't it ever occur that they collide and grab an electron or two ...
5
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0answers
293 views

How to estimate the enrichment of U-234 from the enrichment of U-235?

Fresh nuclear fuel made from naturally occurring uranium (i.e. neither MOX nor ERU fuel) is mainly characterised by the enrichment of $\ce{^235U}$. The mass and activity concentrations of $\ce{^235U}$ ...
4
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1answer
278 views

How does radiocarbon dating work?

I'd like to better understand radiocarbon dating, however, I do not know what resources I must use in this regard. Could someone walk me through the process of radiocarbon dating with a few examples? (...
4
votes
1answer
322 views

When do reactions reach steady state?

I was doing a multiple choice problem that asked about when the following nuclear decay sequence reaches steady state (When does the activity of $\ce{^99Mo}$ roughly equal the activity of $\ce{^{99m}...
4
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0answers
728 views

Is order of reaction defined for nuclear reactions?

I am asking this question after asking a similar one for spontaneous nuclear decay phy.stack. Link Order of reaction is defined for chemical reaction. But wikipedia says about spontaneous nuclear ...
4
votes
1answer
210 views

Rutherford's gold foil experiment [duplicate]

Rutherford projected $\alpha$-rays onto the gold foil. $\alpha$-rays are the same as a $\ce{He^2+}$ nucleus and they can ionize atoms. Therefore, why are gold atoms not ionized when the $\alpha$-rays ...
3
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2answers
3k views

Nuclear power: what material is the control rod made from?

What type of material is used in the control rod of a nuclear reactor? (Nuclear power plant)
3
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2answers
955 views

Notation of beta decay

Is it an ion or a neutral atom that is created through beta decay? For example: $_6^{14}\mathrm C \to ~ _7^{14}\mathrm N + \mathrm e^- + \mathrm{v{_e}}^{-}$ Isn't $_7^{14}N$ an ion since neutron ...
3
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1answer
755 views

What does HTO decay into?

I'm aware that tritium undergoes beta decay forming Helium-3. But in the case of HTO, what does it decay into? I don't suppose it decays into HeHO.
3
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1answer
1k views

What is advantage of creating elements that disappear in a flash?

More than dozen of heavy elements of periodic table do not occur naturally but are prepared artificially at nuclear reactors.. These elements are said to disappear in a flash.. So, why invest lot of ...
3
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1answer
68 views

Instability due to neutrons

Why does an excess of neutrons leads to instability? For example, both $\ce{^{3}H}$ and $\ce{^{4}H}$ are unstable, with respective half-lives of $3.89\cdot 10^8$ and $1.39\cdot 10^{-22}$ seconds. ...
3
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1answer
179 views

Nuclear Fallout [closed]

If there was a nuclear explosion and years later I come out of a fallout shelter like in the popular game series Fallout, what elements would react to the radiation in a way that could harm humans and ...
3
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3answers
4k views

In nuclear chemistry, how does a neutron split to form a proton and an electron?

I'm studying radioisotopes at the moment and balancing nuclear reactions isn't making sense in that more matter is coming out of the equation in negative β⁻ decay equations: $$\ce{_6^{14}C -> _7^{...
3
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0answers
38 views

Why isn't protium nucleus considered most stable nucleus?

My chemistry teacher told me that $\ce{^{56}Fe}$ is the most stable nucleus because of the highest binding energy per nucleon. But if we consider a protium nucleus, it has only 1 proton so there is no ...
3
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1answer
356 views

Uses of ruthenium-106?

I read a news article recently about a cloud of ruthenium-106 being released over Europe. The article mentioned one of the uses for this specific isotope is in fuel cells for satellites. I tried to do ...
2
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4answers
4k views

What is the difference between nuclear fission and nuclear fusion?

I always mix up the definition of nuclear fission and nuclear fusion. So, what is nuclear fission and nuclear fusion, and an example for each?
2
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1answer
834 views

Types of radioactive decay

Besides alpha, beta, and gamma, are there any other types of radioactive decay? If so, what are they? Is there any type of radioactive decay that is more powerful than gamma?
2
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1answer
505 views

Why doesn't the atomic number change by two in the process of production of Americium?

Looking at the bomardment of uranium-238 this is what I see. First, I see a uranium-238 atom with 92 protons bombarded with a neutron. The neutron then undergoes beta decay into a proton. So we then ...
2
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1answer
39 views

Are the electrons also distributed for the alpha decay?

Consider this reaction of alpha decay: $$ \ce{^{222}_{88}Ra -> ^{218}_{86}Rn + ^4_2 He} $$ My question is, whether or not the electrons also get distributed in the reaction like the nucleons?
1
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2answers
88 views

Anti matter elements? [closed]

Quite a self-explanatory question I guess. I wonder whether there is any information or theory on this. I seem to like remember there is such an element with positron in center and electron rotating ...
1
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3answers
133 views

Radioactivity and Kinetics of disintegration

Well I've just started on kinetics and there are a few things I am absolutely confused about! First of all, is a neutron actually made up of a proton and electron? If yes, then how is this possible? ...
1
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2answers
3k views

Where do the electrons that are released in the sun go?

I've heard that electrons are released from the clutches of nuclei in the plasma state that is present in the sun. My question is: Where do these electrons go? Do they go to the product nuclei of the ...
1
vote
1answer
82 views

“Orthogonality” of chemical elements

Chemical elements are said to be immutable at normal energies, but not at the energies that are orders of magnitude higher. Given that nucleus at normal energies gives us the Periodic Table and at ...
1
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1answer
1k views

Final amount of Hg present after $\beta$ decay

I have been trying to solve an exercise on nuclear chemistry, but I was not sure whether I should ask this on physics or chemistry but I think that if chemistry had an exercise based on this then ...
1
vote
1answer
80 views

Find ratio of number of atoms of $A$ and $B$

However I am thinking of this question to be damn easy but still I'll not say as I am not getting it, There are two radio nuclei $A$ and $B$. $A$ is $\alpha$ emitter and $B$ is $\beta$ emitter ...
1
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1answer
101 views

New technology that has replaced the old radioisotope

What technology has the radioisotope Cobalt 60 replaced in medicine? E.g.,PET preferred over CT scans
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0answers
45 views

What happens to chemical bonds if the nucleus changes? [duplicate]

Lets say I have some $\ce{PuF6}$ (with the Plutonium being $\ce{^{240}Pu}$). I take this $\ce{PuF6}$ and bombard it with neutrons. The $\ce{^{240}Pu}$ nuclei capture the neutrons, forming $\ce{^{241}...
1
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3answers
170 views

Intuition for why effective nuclear charge increases down a column

My textbook (Chemistry the Central Science, edition 12, Brown et al.) says that effective nuclear charge increases down a column. Indeed, this is consistent with the values provided by Clementi in the ...
1
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0answers
42 views

What is the most stable pear-shaped nucleus? [closed]

I have heard on the Internet that there are at least three pear-shaped nuclei: radium-224, radon-220 (a direct product of the previous isotope), and barium-144. CERN has a webpage about this discovery ...
0
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3answers
129 views

Why does radioactive matter decay in series of half-lives?

I was studying types of nuclear decay, and I came across the concept of "half-life". And I started wondering why does nuclear matter decay in half-lives? In other words, why does the rate of nuclear ...
0
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3answers
1k views

Can you decay to half an atom?

In school we are learning about half-life, and I was wondering if it is possible to decay to half an atom?
0
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3answers
227 views

Beta Decay - Doesn't Add Up [duplicate]

The definition of beta $(\beta^-)$ decay is that an electron is produced. For example, $$\ce{^131_53I -> ^131_54Xe + e^-}$$ So iodine forms Xe and releases one electron with a -1 charge only and ...
0
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1answer
75 views

Can neutrons be ejected from an atom?

In a neutral atom, can neutrons be ejected, and if so, by what (nuclear) process or reaction? I have read Neutron emission and Can a proton be ejected from an atom, but I don't understand how and if ...
0
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3answers
4k views

Is it possible to compress an atom to infinite density? [closed]

I know, by nature, normally atoms are stable. But I wonder, if it is possible to compress an atom, say the Hydrogen atom, to infinite density by applying external force? After all, electrons and ...
0
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1answer
77 views

Low Energy Nuclear Reactions [closed]

I was interested in knowing if Low Energy Nuclear Reactions are practical or just mythical. What is the current stance of the scientific society about their feasibility?
0
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2answers
648 views

Rutherford gold foil experiment

This question may sound silly. What actually I understood from this experiment is that the positively charged nucleus which is in the center is responsible for the bending and reflection of the alpha ...
0
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1answer
42 views

Size of atomic shells

Is the distance of some $n^{th}$ shell ($n$ $\neq$ outermost shell) from the nucleus of an atom different for different elements? If so, then how much is the difference or how could we calculate it?